diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/ChangeLog | 30 | ||||
| -rw-r--r-- | doc/awkcard.in | 31 | ||||
| -rw-r--r-- | doc/gawk.1 | 16 | ||||
| -rw-r--r-- | doc/gawk.info | 1344 | ||||
| -rw-r--r-- | doc/gawk.texi | 176 | ||||
| -rw-r--r-- | doc/gawktexi.in | 176 |
6 files changed, 1050 insertions, 723 deletions
diff --git a/doc/ChangeLog b/doc/ChangeLog index 8e311ec8..151b03f0 100644 --- a/doc/ChangeLog +++ b/doc/ChangeLog @@ -1,3 +1,29 @@ +2021-05-02 Arnold D. Robbins <arnold@skeeve.com> + + * gawktexi.in, gawk.1, awkcard.in: Renamed bool to mkbool. + +2021-04-28 Arnold D. Robbins <arnold@skeeve.com> + + * gawktexi.in: Revise doc for bools; they're now just numbers + with an extra flag. + * gawk.1: Ditto. + * awkcard.in: Ditto. + +2021-04-14 Arnold D. Robbins <arnold@skeeve.com> + + * gawktexi.in (Controlling Scanning): Document bools for + "@val_type_asc". + * awkcard.in: Add doc on bool() function. + +2021-04-06 Arnold D. Robbins <arnold@skeeve.com> + + * gawktexi.in: Finish documenting bool features. + * gawk.1: Add minimal documentation on bool. + +2021-04-04 Arnold D. Robbins <arnold@skeeve.com> + + * gawktexi.in: Start documenting bool features. + 2021-04-04 Arnold D. Robbins <arnold@skeeve.com> * gawktexi.in: Update menues. @@ -9,6 +35,10 @@ <arkadiusz@drabczyk.org> for pointing out the lack of documentation. +2021-03-22 Arnold D. Robbins <arnold@skeeve.com> + + * gawktexi.in (Constructor Functions): Add doc on `make_bool'. + 2021-03-21 Arnold D. Robbins <arnold@skeeve.com> * gawktexi.in (Other Environment Variables): Document "fnv1a" diff --git a/doc/awkcard.in b/doc/awkcard.in index 7cf90cc7..659a4a72 100644 --- a/doc/awkcard.in +++ b/doc/awkcard.in @@ -2,7 +2,7 @@ .\" .\" Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, .\" 2005, 2007, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, -.\" 2019, 2020 +.\" 2019, 2020, 2021 .\" Free Software Foundation, Inc. .\" .\" Permission is granted to make and distribute verbatim copies of @@ -100,7 +100,7 @@ Variables 5\*(CX \*(CD .SL .nf -\*(FRCopyright \(co 1996\(en2005, 2007, 2009\(en2020 +\*(FRCopyright \(co 1996\(en2005, 2007, 2009\(en2021 Free Software Foundation, Inc. .nf .BT @@ -1916,6 +1916,19 @@ See the manual for details.\*(CB .EB "\s+2\f(HBDYNAMIC EXTENSIONS (\*(GK\f(HB)\*(FR\s0" .BT +.\" --- Generator Functions +.ES +.fi +.in +.2i +.ti -.2i +\*(CD\*(FCmkbool(\*(FIexpression\*(FC)\*(FR +.br +Return a Boolean-typed value based on the Boolean value +of \*(FIexpression\fP. True values have a numeric value of one. +False values have a numeric value of zero.\*(CB +.in -.2i +.EB "\s+2\f(HBGENERATOR FUNCTIONS (\*(GK\f(HB)\*(FR\s0" +.sp .5 .\" --- Type Functions .ES .fi @@ -1959,11 +1972,6 @@ Return the translation of \*(FIstring\*(FR in text domain \*(FIdomain\*(FR for locale category \*(FIcategory\*(FR. The default value for \*(FIdomain\*(FR is the current value of \*(FCTEXTDOMAIN\*(FR. The default value for \*(FIcategory\*(FR is \*(FC"LC_MESSAGES"\*(FR. -.sp .5 -If you supply a value for \*(FIcategory\*(FR, it must be a string equal to -one of the known locale categories. -You must also supply a text domain. Use \*(FCTEXTDOMAIN\*(FR -to use the current domain. .ti -.2i \*(FCdcngettext(\*(FIstring1\*(FC, \*(FIstring2\*(FC, \*(FInumber\*(FR [\*(FC, \*(FIdom \*(FR[\*(FC, \*(FIcat\*(FR]]\*(FC)\*(FR .br @@ -1971,12 +1979,7 @@ Return the plural form used for \*(FInumber\*(FR of the translation of \*(FIstring1\*(FR and \*(FIstring2\*(FR in text domain \*(FIdom\*(FR for locale category \*(FIcat\*(FR. The default value for \*(FIdom\*(FR is the current value of \*(FCTEXTDOMAIN\*(FR. -The default for \*(FIcat\*(FR is \*(FC"LC_MESSAGES"\*(FR. -.sp .5 -If you supply a value for \*(FIcat\*(FR, it must be a string equal to -one of the known locale categories. -You must also supply a text domain. Use \*(FCTEXTDOMAIN\*(FR -to use the current domain.\*(CB +The default for \*(FIcat\*(FR is \*(FC"LC_MESSAGES"\*(FR.\*(CB .in -.2i .EB "\s+2\f(HBINTERNATIONALIZATION (\*(GK\f(HB)\*(FR\s0" .sp .5 @@ -2012,7 +2015,7 @@ maintains it.\*(CX .ES .fi \*(CDCopyright \(co 1996\(en2005, -2007, 2009\(en2020 Free Software Foundation, Inc. +2007, 2009\(en2021 Free Software Foundation, Inc. .sp .5 Permission is granted to make and distribute verbatim copies of this reference card provided the copyright notice and this permission notice @@ -13,7 +13,7 @@ . if \w'\(rq' .ds rq "\(rq . \} .\} -.TH GAWK 1 "Aug 31 2020" "Free Software Foundation" "Utility Commands" +.TH GAWK 1 "May 02 2021" "Free Software Foundation" "Utility Commands" .SH NAME gawk \- pattern scanning and processing language .SH SYNOPSIS @@ -3480,6 +3480,16 @@ in \*(EP. You must also supply a text domain. Use .B TEXTDOMAIN if you want to use the current domain. +.SS Boolean Valued Functions +You can create special Boolean-typed values; see the manual for how +they work and why they exist. +.TP +.BI mkbool( expression\^ ) +Based on the boolean value of +.I expression +return either a true value or a false value. +True values have numeric value one. +False values have numeric value zero. .SH USER-DEFINED FUNCTIONS Functions in \*(AK are defined as follows: .PP @@ -3700,7 +3710,7 @@ accommodate applications that depended upon the old behavior. (This feature was agreed upon by both the Bell Laboratories developers and the \*(GN developers.) .PP -When processing arguments, +When procesiing arguments, .I gawk uses the special option \*(lq\-\^\-\*(rq to signal the end of arguments. @@ -4265,7 +4275,7 @@ We thank him. .SH COPYING PERMISSIONS Copyright \(co 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2001, 2002, 2003, 2004, 2005, 2007, 2009, -2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, +2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, Free Software Foundation, Inc. .PP Permission is granted to make and distribute verbatim copies of diff --git a/doc/gawk.info b/doc/gawk.info index f5f417a6..824d78e7 100644 --- a/doc/gawk.info +++ b/doc/gawk.info @@ -381,6 +381,8 @@ in (a) below. A copy of the license is included in the section entitled * Arrays Summary:: Summary of arrays. * Built-in:: Summarizes the built-in functions. * Calling Built-in:: How to call built-in functions. +* Boolean Functions:: A function that returns Boolean + values. * Numeric Functions:: Functions that work with numbers, including 'int()', 'sin()' and 'rand()'. @@ -488,6 +490,7 @@ in (a) below. A copy of the license is included in the section entitled * Programs Summary:: Summary of programs. * Programs Exercises:: Exercises. * Nondecimal Data:: Allowing nondecimal input data. +* Boolean Typed Values:: Values with 'bool' type. * Array Sorting:: Facilities for controlling array traversal and sorting arrays. * Controlling Array Traversal:: How to use PROCINFO["sorted_in"]. @@ -12782,6 +12785,7 @@ your convenience. * Menu: * Calling Built-in:: How to call built-in functions. +* Boolean Functions:: A function that returns Boolean values. * Numeric Functions:: Functions that work with numbers, including 'int()', 'sin()' and 'rand()'. * String Functions:: Functions for string manipulation, such as @@ -12794,7 +12798,7 @@ your convenience. * I18N Functions:: Functions for string translation. -File: gawk.info, Node: Calling Built-in, Next: Numeric Functions, Up: Built-in +File: gawk.info, Node: Calling Built-in, Next: Boolean Functions, Up: Built-in 9.1.1 Calling Built-in Functions -------------------------------- @@ -12838,9 +12842,24 @@ six, and then 12, and 'atan2()' is called with the two arguments six and 10, then 11, and 'atan2()' is called with the two arguments 11 and 10. -File: gawk.info, Node: Numeric Functions, Next: String Functions, Prev: Calling Built-in, Up: Built-in +File: gawk.info, Node: Boolean Functions, Next: Numeric Functions, Prev: Calling Built-in, Up: Built-in -9.1.2 Numeric Functions +9.1.2 Generating Boolean Values +------------------------------- + +This function is specific to 'gawk'. It is not available in +compatibility mode (*note Options::): + +'bmkool(EXPRESSION)' + Return a Boolean-typed value based on the regular Boolean value of + EXPRESSION. Boolean "true" values have numeric value one. Boolean + "false" values have numeric zero. This is discussed in more detail + in *note Boolean Typed Values::. + + +File: gawk.info, Node: Numeric Functions, Next: String Functions, Prev: Boolean Functions, Up: Built-in + +9.1.3 Numeric Functions ----------------------- The following list describes all of the built-in functions that work @@ -12964,7 +12983,7 @@ the same sequence of random numbers over and over again. File: gawk.info, Node: String Functions, Next: I/O Functions, Prev: Numeric Functions, Up: Built-in -9.1.3 String-Manipulation Functions +9.1.4 String-Manipulation Functions ----------------------------------- The functions in this minor node look at or change the text of one or @@ -13532,7 +13551,7 @@ number zero. File: gawk.info, Node: Gory Details, Up: String Functions -9.1.3.1 More about '\' and '&' with 'sub()', 'gsub()', and 'gensub()' +9.1.4.1 More about '\' and '&' with 'sub()', 'gsub()', and 'gensub()' ..................................................................... CAUTION: This subsubsection has been reported to cause headaches. @@ -13678,7 +13697,7 @@ POSIX rules. File: gawk.info, Node: I/O Functions, Next: Time Functions, Prev: String Functions, Up: Built-in -9.1.4 Input/Output Functions +9.1.5 Input/Output Functions ---------------------------- The following functions relate to input/output (I/O). Optional @@ -13895,7 +13914,7 @@ the way this was done was probably a mistake. File: gawk.info, Node: Time Functions, Next: Bitwise Functions, Prev: I/O Functions, Up: Built-in -9.1.5 Time Functions +9.1.6 Time Functions -------------------- 'awk' programs are commonly used to process log files containing @@ -14212,7 +14231,7 @@ does not appear in the returned string or appears literally. File: gawk.info, Node: Bitwise Functions, Next: Type Functions, Prev: Time Functions, Up: Built-in -9.1.6 Bit-Manipulation Functions +9.1.7 Bit-Manipulation Functions -------------------------------- I can explain it for you, but I can't understand it for you. @@ -14394,7 +14413,7 @@ that range are reduced to fit within the range. File: gawk.info, Node: Type Functions, Next: I18N Functions, Prev: Bitwise Functions, Up: Built-in -9.1.7 Getting Type Information +9.1.8 Getting Type Information ------------------------------ 'gawk' provides two functions that let you distinguish the type of a @@ -14418,6 +14437,9 @@ contexts. '"number"' X is a number. + '"number|bool"' + X is a Boolean typed value (*note Boolean Typed Values::). + '"string"' X is a string. @@ -14479,7 +14501,7 @@ arguments from untyped to unassigned. File: gawk.info, Node: I18N Functions, Prev: Type Functions, Up: Built-in -9.1.8 String-Translation Functions +9.1.9 String-Translation Functions ---------------------------------- 'gawk' provides facilities for internationalizing 'awk' programs. These @@ -15158,7 +15180,7 @@ File: gawk.info, Node: Indirect Calls, Next: Functions Summary, Prev: User-de 9.3 Indirect Function Calls =========================== -This section describes an advanced, 'gawk'-specific extension. +This minor node describes an advanced, 'gawk'-specific extension. Often, you may wish to defer the choice of function to call until runtime. For example, you may have different kinds of records, each of @@ -20873,6 +20895,7 @@ their own: * Menu: * Nondecimal Data:: Allowing nondecimal input data. +* Boolean Typed Values:: Values with 'number|bool' type. * Array Sorting:: Facilities for controlling array traversal and sorting arrays. * Two-way I/O:: Two-way communications with another process. @@ -20882,7 +20905,7 @@ their own: * Advanced Features Summary:: Summary of advanced features. -File: gawk.info, Node: Nondecimal Data, Next: Array Sorting, Up: Advanced Features +File: gawk.info, Node: Nondecimal Data, Next: Boolean Typed Values, Up: Advanced Features 12.1 Allowing Nondecimal Input Data =================================== @@ -20925,9 +20948,53 @@ request it. This option may disappear in a future version of 'gawk'. -File: gawk.info, Node: Array Sorting, Next: Two-way I/O, Prev: Nondecimal Data, Up: Advanced Features +File: gawk.info, Node: Boolean Typed Values, Next: Array Sorting, Prev: Nondecimal Data, Up: Advanced Features + +12.2 Boolean Typed Values +========================= + +Scalar values in 'awk' are either numbers or strings. 'gawk' also +supports values of type 'regexp' (*note Strong Regexp Constants::). + + As described in *note Truth Values::, Boolean values in 'awk' don't +have a separate type: a value counts as "true" if it is nonzero or +non-null, and as "false" otherwise. + + When interchanging data with languages that do have a real Boolean +type, using a standard format such as JSON or XML, the lack of a true +Boolean type in 'awk' is problematic. (See, for example, the 'json' +extension provided by the 'gawkextlib' project +(https://sourceforge.net/projects/gawkextlib).) + + It's easy to import Boolean data into 'awk', but then the fact that +it was originally Boolean is lost. Exporting data is even harder; +there's no way to indicate that a value is really Boolean. + + To solve this problem, 'gawk' provides a function named 'mkbool()'. +It takes one argument, which is any 'awk' expression, and it returns a +value of Boolean type. + + The returned values are normal 'awk' numeric values, with values of +either one or zero, depending upon the truth value of the original +expression passed in the call to 'bool()'. + + The 'typeof()' function (*note Type Functions::) returns +'"number|bool"' for these values. + + Thus Boolean-typed values _are_ numbers as far as 'gawk' is +concerned, except that extension code can treat them as Booleans if +desired. + + While it would have been possible to add two new built-in variables +of Boolean type named 'TRUE' and 'FALSE', doing so would undoubtedly +have broken many existing 'awk' programs. Instead, having a "generator" +function that creates Boolean values gives flexibility, without breaking +as much existing code. + + +File: gawk.info, Node: Array Sorting, Next: Two-way I/O, Prev: Boolean Typed Values, Up: Advanced Features -12.2 Controlling Array Traversal and Array Sorting +12.3 Controlling Array Traversal and Array Sorting ================================================== 'gawk' lets you control the order in which a 'for (INDX in ARRAY)' loop @@ -20946,7 +21013,7 @@ to order the elements during sorting. File: gawk.info, Node: Controlling Array Traversal, Next: Array Sorting Functions, Up: Array Sorting -12.2.1 Controlling Array Traversal +12.3.1 Controlling Array Traversal ---------------------------------- By default, the order in which a 'for (INDX in ARRAY)' loop scans an @@ -21185,7 +21252,7 @@ character, which cannot be part of an identifier. File: gawk.info, Node: Array Sorting Functions, Prev: Controlling Array Traversal, Up: Array Sorting -12.2.2 Sorting Array Values and Indices with 'gawk' +12.3.2 Sorting Array Values and Indices with 'gawk' --------------------------------------------------- In most 'awk' implementations, sorting an array requires writing a @@ -21325,7 +21392,7 @@ POSIX-compatibility mode, and because 'asort()' and 'asorti()' are File: gawk.info, Node: Two-way I/O, Next: TCP/IP Networking, Prev: Array Sorting, Up: Advanced Features -12.3 Two-Way Communications with Another Process +12.4 Two-Way Communications with Another Process ================================================ It is often useful to be able to send data to a separate program for @@ -21520,7 +21587,7 @@ in Bash. File: gawk.info, Node: TCP/IP Networking, Next: Profiling, Prev: Two-way I/O, Up: Advanced Features -12.4 Using 'gawk' for Network Programming +12.5 Using 'gawk' for Network Programming ========================================= 'EMRED': @@ -21600,7 +21667,7 @@ complete introduction and discussion, as well as extensive examples. File: gawk.info, Node: Profiling, Next: Extension Philosophy, Prev: TCP/IP Networking, Up: Advanced Features -12.5 Profiling Your 'awk' Programs +12.6 Profiling Your 'awk' Programs ================================== You may produce execution traces of your 'awk' programs. This is done @@ -21862,7 +21929,7 @@ source code, it will appear that way in the output. File: gawk.info, Node: Extension Philosophy, Next: Advanced Features Summary, Prev: Profiling, Up: Advanced Features -12.6 Builtin Features versus Extensions +12.7 Builtin Features versus Extensions ======================================= As this and subsequent major nodes show, 'gawk' has a large number of @@ -21898,7 +21965,7 @@ or need. File: gawk.info, Node: Advanced Features Summary, Prev: Extension Philosophy, Up: Advanced Features -12.7 Summary +12.8 Summary ============ * The '--non-decimal-data' option causes 'gawk' to treat octal- and @@ -25520,7 +25587,8 @@ use them. ' AWK_STRNUM,' ' AWK_ARRAY,' ' AWK_SCALAR, /* opaque access to a variable */' -' AWK_VALUE_COOKIE /* for updating a previously created value */' +' AWK_VALUE_COOKIE, /* for updating a previously created value */' +' AWK_BOOL' '} awk_valtype_t;' This 'enum' indicates the type of a value. It is used in the following 'struct'. @@ -25533,6 +25601,7 @@ use them. ' awk_array_t a;' ' awk_scalar_t scl;' ' awk_value_cookie_t vc;' +' awk_bool_t b;' ' } u;' '} awk_value_t;' An "'awk' value." The 'val_type' member indicates what kind of @@ -25548,6 +25617,7 @@ use them. '#define array_cookie u.a' '#define scalar_cookie u.scl' '#define value_cookie u.vc' +'#define bool_value u.b' Using these macros makes accessing the fields of the 'awk_value_t' more readable. @@ -25858,6 +25928,11 @@ code would use them: a 'char *' value pointing to data previously obtained from 'gawk_malloc()', 'gawk_calloc()', or 'gawk_realloc()'. +'static inline awk_value_t *' +'make_bool(awk_bool_t boolval, awk_value_t *result);' + This function creates a boolean value in the 'awk_value_t' variable + pointed to by 'result'. + File: gawk.info, Node: API Ownership of MPFR and GMP Values, Next: Registration Functions, Prev: Constructor Functions, Up: Extension API Description @@ -26583,16 +26658,17 @@ summarized in *note Table 17.2: table-value-types-returned. Type of Actual Value -------------------------------------------------------------------------- - String Strnum Number Regex Array Undefined -------------------------------------------------------------------------------- - String String String String String false false - Strnum false Strnum Strnum false false false - Number Number Number Number false false false -Type Regex false false false Regex false false -Requested Array false false false false Array false - Scalar Scalar Scalar Scalar Scalar false false - Undefined String Strnum Number Regex Array Undefined - Value false false false false false false + String Strnum Number Regex Bool Array Undefined +---------------------------------------------------------------------------------------- + String String String String String String false false + Strnum false Strnum Strnum false false false false + Number Number Number Number false Number false false +Type Regex false false false Regex false false false +Requested Bool false false false false Bool false false + Array false false false false false Array false + Scalar Scalar Scalar Scalar Scalar Scalar false false + Undefined String Strnum Number Regex Bool Array Undefined + Value false false false false false false false cookie Table 17.2: API value types returned @@ -33152,8 +33228,8 @@ Localization Logical Expression An expression using the operators for logic, AND, OR, and NOT, - written '&&', '||', and '!' in 'awk'. Often called Boolean - expressions, after the mathematician who pioneered this kind of + written '&&', '||', and '!' in 'awk'. Often called "Boolean + expressions", after the mathematician who pioneered this kind of mathematical logic. Lvalue @@ -35310,6 +35386,7 @@ Index * body, in loops: While Statement. (line 14) * Boolean expressions: Boolean Ops. (line 6) * Boolean expressions, as patterns: Expression Patterns. (line 39) +* boolean function: Boolean Functions. (line 6) * Bourne shell, quoting rules for: Quoting. (line 18) * braces ({}), regexp operator: Regexp Operator Details. (line 118) @@ -36898,6 +36975,7 @@ Index * metacharacters, escape sequences for: Escape Sequences. (line 140) * metacharacters, in regular expressions: Regexp Operators. (line 6) * minimum precision required by MPFR library: Auto-set. (line 279) +* mkbool: Boolean Functions. (line 10) * mktime: Time Functions. (line 25) * modifiers, in format specifiers: Format Modifiers. (line 6) * module, definition of: Global Namespace. (line 18) @@ -38116,604 +38194,606 @@ Index Tag Table: Node: Top1200 -Node: Foreword344859 -Node: Foreword449301 -Node: Preface50833 -Ref: Preface-Footnote-153692 -Ref: Preface-Footnote-253801 -Ref: Preface-Footnote-354035 -Node: History54177 -Node: Names56529 -Ref: Names-Footnote-157633 -Node: This Manual57780 -Ref: This Manual-Footnote-164419 -Node: Conventions64519 -Node: Manual History66888 -Ref: Manual History-Footnote-169885 -Ref: Manual History-Footnote-269926 -Node: How To Contribute70000 -Node: Acknowledgments70926 -Node: Getting Started75863 -Node: Running gawk78302 -Node: One-shot79492 -Node: Read Terminal80755 -Node: Long82748 -Node: Executable Scripts84261 -Ref: Executable Scripts-Footnote-186894 -Node: Comments86997 -Node: Quoting89481 -Node: DOS Quoting95007 -Node: Sample Data Files97063 -Node: Very Simple99658 -Node: Two Rules105760 -Node: More Complex107645 -Node: Statements/Lines109977 -Ref: Statements/Lines-Footnote-1114461 -Node: Other Features114726 -Node: When115662 -Ref: When-Footnote-1117416 -Node: Intro Summary117481 -Node: Invoking Gawk118365 -Node: Command Line119879 -Node: Options120677 -Ref: Options-Footnote-1138591 -Ref: Options-Footnote-2138822 -Node: Other Arguments138847 -Node: Naming Standard Input142858 -Node: Environment Variables144068 -Node: AWKPATH Variable144626 -Ref: AWKPATH Variable-Footnote-1148038 -Ref: AWKPATH Variable-Footnote-2148072 -Node: AWKLIBPATH Variable148443 -Ref: AWKLIBPATH Variable-Footnote-1150140 -Node: Other Environment Variables150515 -Node: Exit Status154467 -Node: Include Files155144 -Node: Loading Shared Libraries158834 -Node: Obsolete160262 -Node: Undocumented160954 -Node: Invoking Summary161251 -Node: Regexp164092 -Node: Regexp Usage165546 -Node: Escape Sequences167583 -Node: Regexp Operators173824 -Node: Regexp Operator Details174309 -Ref: Regexp Operator Details-Footnote-1181673 -Node: Interval Expressions181820 -Ref: Interval Expressions-Footnote-1183241 -Node: Bracket Expressions183339 -Ref: table-char-classes185815 -Node: Leftmost Longest189141 -Node: Computed Regexps190444 -Node: GNU Regexp Operators193871 -Node: Case-sensitivity197608 -Ref: Case-sensitivity-Footnote-1200474 -Ref: Case-sensitivity-Footnote-2200709 -Node: Regexp Summary200817 -Node: Reading Files202283 -Node: Records204552 -Node: awk split records205627 -Node: gawk split records210327 -Ref: gawk split records-Footnote-1215401 -Node: Fields215438 -Node: Nonconstant Fields218179 -Ref: Nonconstant Fields-Footnote-1220415 -Node: Changing Fields220619 -Node: Field Separators226650 -Node: Default Field Splitting229348 -Node: Regexp Field Splitting230466 -Node: Single Character Fields234143 -Node: Command Line Field Separator235203 -Node: Full Line Fields238421 -Ref: Full Line Fields-Footnote-1239943 -Ref: Full Line Fields-Footnote-2239989 -Node: Field Splitting Summary240090 -Node: Constant Size242164 -Node: Fixed width data242896 -Node: Skipping intervening246363 -Node: Allowing trailing data247161 -Node: Fields with fixed data248198 -Node: Splitting By Content249716 -Ref: Splitting By Content-Footnote-1253499 -Node: More CSV253662 -Node: Testing field creation255254 -Node: Multiple Line256879 -Node: Getline263156 -Node: Plain Getline265625 -Node: Getline/Variable268198 -Node: Getline/File269349 -Node: Getline/Variable/File270737 -Ref: Getline/Variable/File-Footnote-1272342 -Node: Getline/Pipe272430 -Node: Getline/Variable/Pipe275134 -Node: Getline/Coprocess276269 -Node: Getline/Variable/Coprocess277536 -Node: Getline Notes278278 -Node: Getline Summary281075 -Ref: table-getline-variants281499 -Node: Read Timeout282247 -Ref: Read Timeout-Footnote-1286153 -Node: Retrying Input286211 -Node: Command-line directories287410 -Node: Input Summary288316 -Node: Input Exercises291488 -Node: Printing291922 -Node: Print293756 -Node: Print Examples295213 -Node: Output Separators297993 -Node: OFMT300010 -Node: Printf301366 -Node: Basic Printf302151 -Node: Control Letters303725 -Node: Format Modifiers308887 -Node: Printf Examples314902 -Node: Redirection317388 -Node: Special FD324229 -Ref: Special FD-Footnote-1327397 -Node: Special Files327471 -Node: Other Inherited Files328088 -Node: Special Network329089 -Node: Special Caveats329949 -Node: Close Files And Pipes330898 -Ref: table-close-pipe-return-values337805 -Ref: Close Files And Pipes-Footnote-1338618 -Ref: Close Files And Pipes-Footnote-2338766 -Node: Nonfatal338918 -Node: Output Summary341256 -Node: Output Exercises342478 -Node: Expressions343157 -Node: Values344345 -Node: Constants345023 -Node: Scalar Constants345714 -Ref: Scalar Constants-Footnote-1348224 -Node: Nondecimal-numbers348474 -Node: Regexp Constants351475 -Node: Using Constant Regexps352001 -Node: Standard Regexp Constants352623 -Node: Strong Regexp Constants355811 -Node: Variables358823 -Node: Using Variables359480 -Node: Assignment Options361390 -Node: Conversion363861 -Node: Strings And Numbers364385 -Ref: Strings And Numbers-Footnote-1367448 -Node: Locale influences conversions367557 -Ref: table-locale-affects370315 -Node: All Operators370933 -Node: Arithmetic Ops371562 -Node: Concatenation374278 -Ref: Concatenation-Footnote-1377125 -Node: Assignment Ops377232 -Ref: table-assign-ops382223 -Node: Increment Ops383536 -Node: Truth Values and Conditions386996 -Node: Truth Values388070 -Node: Typing and Comparison389118 -Node: Variable Typing389938 -Ref: Variable Typing-Footnote-1396401 -Ref: Variable Typing-Footnote-2396473 -Node: Comparison Operators396550 -Ref: table-relational-ops396969 -Node: POSIX String Comparison400464 -Ref: POSIX String Comparison-Footnote-1402159 -Ref: POSIX String Comparison-Footnote-2402298 -Node: Boolean Ops402382 -Ref: Boolean Ops-Footnote-1406864 -Node: Conditional Exp406956 -Node: Function Calls408692 -Node: Precedence412569 -Node: Locales416228 -Node: Expressions Summary417860 -Node: Patterns and Actions420433 -Node: Pattern Overview421553 -Node: Regexp Patterns423230 -Node: Expression Patterns423772 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Functions668056 +Ref: Ordinal Functions-Footnote-1671119 +Ref: Ordinal Functions-Footnote-2671371 +Node: Join Function671581 +Ref: Join Function-Footnote-1673351 +Node: Getlocaltime Function673551 +Node: Readfile Function677293 +Node: Shell Quoting679270 +Node: Data File Management680671 +Node: Filetrans Function681303 +Node: Rewind Function685399 +Node: File Checking687308 +Ref: File Checking-Footnote-1688642 +Node: Empty Files688843 +Node: Ignoring Assigns690822 +Node: Getopt Function692372 +Ref: Getopt Function-Footnote-1707583 +Node: Passwd Functions707783 +Ref: Passwd Functions-Footnote-1716622 +Node: Group Functions716710 +Ref: Group Functions-Footnote-1724608 +Node: Walking Arrays724815 +Node: Library Functions Summary727823 +Node: Library Exercises729229 +Node: Sample Programs729694 +Node: Running Examples730464 +Node: Clones731192 +Node: Cut Program732416 +Node: Egrep Program742556 +Node: Id Program751557 +Node: Split Program761504 +Ref: Split Program-Footnote-1771394 +Node: Tee Program771567 +Node: Uniq Program774357 +Node: Wc Program781945 +Node: Bytes vs. Characters782332 +Node: Using extensions783880 +Node: wc program784634 +Node: Miscellaneous Programs789499 +Node: Dupword Program790712 +Node: Alarm Program792742 +Node: Translate Program797597 +Ref: Translate Program-Footnote-1802162 +Node: Labels Program802432 +Ref: Labels Program-Footnote-1805783 +Node: Word Sorting805867 +Node: History Sorting809939 +Node: Extract Program812164 +Node: Simple Sed820218 +Node: Igawk Program823292 +Ref: Igawk Program-Footnote-1837623 +Ref: Igawk Program-Footnote-2837825 +Ref: Igawk Program-Footnote-3837947 +Node: Anagram Program838062 +Node: Signature Program841124 +Node: Programs Summary842371 +Node: Programs Exercises843585 +Ref: Programs Exercises-Footnote-1847715 +Node: Advanced Features847801 +Node: Nondecimal Data849932 +Node: Boolean Typed Values851530 +Node: Array Sorting853409 +Node: Controlling Array Traversal854114 +Ref: Controlling Array Traversal-Footnote-1862482 +Node: Array Sorting Functions862600 +Ref: Array Sorting Functions-Footnote-1867691 +Node: Two-way I/O867887 +Ref: Two-way I/O-Footnote-1875608 +Ref: Two-way I/O-Footnote-2875795 +Node: TCP/IP Networking875877 +Node: Profiling878995 +Node: Extension Philosophy888304 +Node: Advanced Features Summary889783 +Node: Internationalization891798 +Node: I18N and L10N893278 +Node: Explaining gettext893965 +Ref: Explaining gettext-Footnote-1899857 +Ref: Explaining gettext-Footnote-2900042 +Node: Programmer i18n900207 +Ref: Programmer i18n-Footnote-1905156 +Node: Translator i18n905205 +Node: String Extraction905999 +Ref: String Extraction-Footnote-1907131 +Node: Printf Ordering907217 +Ref: Printf Ordering-Footnote-1910003 +Node: I18N Portability910067 +Ref: I18N Portability-Footnote-1912523 +Node: I18N Example912586 +Ref: I18N Example-Footnote-1915861 +Ref: I18N Example-Footnote-2915934 +Node: Gawk I18N916043 +Node: I18N Summary916692 +Node: Debugger918033 +Node: Debugging919033 +Node: Debugging Concepts919474 +Node: Debugging Terms921283 +Node: Awk Debugging923858 +Ref: Awk Debugging-Footnote-1924803 +Node: Sample Debugging Session924935 +Node: Debugger Invocation925469 +Node: Finding The Bug926855 +Node: List of Debugger Commands933329 +Node: Breakpoint Control934662 +Node: Debugger Execution Control938356 +Node: Viewing And Changing Data941718 +Node: Execution Stack945259 +Node: Debugger Info946896 +Node: Miscellaneous Debugger Commands950967 +Node: Readline Support956029 +Node: Limitations956925 +Node: Debugging Summary959479 +Node: Namespaces960758 +Node: Global Namespace961869 +Node: Qualified Names963267 +Node: Default Namespace964266 +Node: Changing The Namespace965007 +Node: Naming Rules966621 +Node: Internal Name Management968469 +Node: Namespace Example969511 +Node: Namespace And Features972073 +Node: Namespace Summary973508 +Node: Arbitrary Precision Arithmetic974985 +Node: Computer Arithmetic976472 +Ref: table-numeric-ranges980238 +Ref: table-floating-point-ranges980731 +Ref: Computer Arithmetic-Footnote-1981389 +Node: Math Definitions981446 +Ref: table-ieee-formats984422 +Node: MPFR features984989 +Node: FP Math Caution986707 +Ref: FP Math Caution-Footnote-1987779 +Node: Inexactness of computations988148 +Node: Inexact representation989179 +Node: Comparing FP Values990539 +Node: Errors accumulate991780 +Node: Strange values993236 +Ref: Strange values-Footnote-1995824 +Node: Getting Accuracy995929 +Node: Try To Round998639 +Node: Setting precision999538 +Ref: table-predefined-precision-strings1000235 +Node: Setting the rounding mode1002065 +Ref: table-gawk-rounding-modes1002439 +Ref: Setting the rounding mode-Footnote-11006370 +Node: Arbitrary Precision Integers1006549 +Ref: Arbitrary Precision Integers-Footnote-11009724 +Node: Checking for MPFR1009873 +Node: POSIX Floating Point Problems1011347 +Ref: POSIX Floating Point Problems-Footnote-11015632 +Node: Floating point summary1015670 +Node: Dynamic Extensions1017860 +Node: Extension Intro1019413 +Node: Plugin License1020679 +Node: Extension Mechanism Outline1021476 +Ref: figure-load-extension1021915 +Ref: figure-register-new-function1023480 +Ref: figure-call-new-function1024572 +Node: Extension API Description1026634 +Node: Extension API Functions Introduction1028347 +Ref: table-api-std-headers1030183 +Node: General Data Types1034432 +Ref: General Data Types-Footnote-11043138 +Node: Memory Allocation Functions1043437 +Ref: Memory Allocation Functions-Footnote-11047938 +Node: Constructor Functions1048037 +Node: API Ownership of MPFR and GMP Values1051690 +Node: Registration Functions1053003 +Node: Extension Functions1053703 +Node: Exit Callback Functions1059025 +Node: Extension Version String1060275 +Node: Input Parsers1060938 +Node: Output Wrappers1073659 +Node: Two-way processors1078171 +Node: Printing Messages1080436 +Ref: Printing Messages-Footnote-11081607 +Node: Updating ERRNO1081760 +Node: Requesting Values1082499 +Ref: table-value-types-returned1083236 +Node: Accessing Parameters1084344 +Node: Symbol Table Access1085581 +Node: Symbol table by name1086093 +Ref: Symbol table by name-Footnote-11089117 +Node: Symbol table by cookie1089245 +Ref: Symbol table by cookie-Footnote-11093430 +Node: Cached values1093494 +Ref: Cached values-Footnote-11097030 +Node: Array Manipulation1097183 +Ref: Array Manipulation-Footnote-11098274 +Node: Array Data Types1098311 +Ref: Array Data Types-Footnote-11100969 +Node: Array Functions1101061 +Node: Flattening Arrays1105559 +Node: Creating Arrays1112535 +Node: Redirection API1117302 +Node: Extension API Variables1120135 +Node: Extension Versioning1120846 +Ref: gawk-api-version1121275 +Node: Extension GMP/MPFR Versioning1123006 +Node: Extension API Informational Variables1124634 +Node: Extension API Boilerplate1125707 +Node: Changes from API V11129681 +Node: Finding Extensions1131253 +Node: Extension Example1131812 +Node: Internal File Description1132610 +Node: Internal File Ops1136690 +Ref: Internal File Ops-Footnote-11148040 +Node: Using Internal File Ops1148180 +Ref: Using Internal File Ops-Footnote-11150563 +Node: Extension Samples1150837 +Node: Extension Sample File Functions1152366 +Node: Extension Sample Fnmatch1160015 +Node: Extension Sample Fork1161502 +Node: Extension Sample Inplace1162720 +Node: Extension Sample Ord1166346 +Node: Extension Sample Readdir1167182 +Ref: table-readdir-file-types1168071 +Node: Extension Sample Revout1169138 +Node: Extension Sample Rev2way1169727 +Node: Extension Sample Read write array1170467 +Node: Extension Sample Readfile1172409 +Node: Extension Sample Time1173504 +Node: Extension Sample API Tests1175256 +Node: gawkextlib1175748 +Node: Extension summary1178666 +Node: Extension Exercises1182368 +Node: Language History1183610 +Node: V7/SVR3.11185266 +Node: SVR41187418 +Node: POSIX1188852 +Node: BTL1190233 +Node: POSIX/GNU1190962 +Node: Feature History1196740 +Node: Common Extensions1213059 +Node: Ranges and Locales1214342 +Ref: Ranges and Locales-Footnote-11218958 +Ref: Ranges and Locales-Footnote-21218985 +Ref: Ranges and Locales-Footnote-31219220 +Node: Contributors1219443 +Node: History summary1225440 +Node: Installation1226820 +Node: Gawk Distribution1227764 +Node: Getting1228248 +Node: Extracting1229211 +Node: Distribution contents1230849 +Node: Unix Installation1237329 +Node: Quick Installation1238011 +Node: Shell Startup Files1240425 +Node: Additional Configuration Options1241514 +Node: Configuration Philosophy1243829 +Node: Non-Unix Installation1246198 +Node: PC Installation1246658 +Node: PC Binary Installation1247496 +Node: PC Compiling1247931 +Node: PC Using1249048 +Node: Cygwin1252601 +Node: MSYS1253825 +Node: VMS Installation1254427 +Node: VMS Compilation1255218 +Ref: VMS Compilation-Footnote-11256447 +Node: VMS Dynamic Extensions1256505 +Node: VMS Installation Details1258190 +Node: VMS Running1260443 +Node: VMS GNV1264722 +Node: VMS Old Gawk1265457 +Node: Bugs1265928 +Node: Bug address1266591 +Node: Usenet1269573 +Node: Maintainers1270577 +Node: Other Versions1271762 +Node: Installation summary1279627 +Node: Notes1280836 +Node: Compatibility Mode1281630 +Node: Additions1282412 +Node: Accessing The Source1283337 +Node: Adding Code1284774 +Node: New Ports1290993 +Node: Derived Files1295368 +Ref: Derived Files-Footnote-11301028 +Ref: Derived Files-Footnote-21301063 +Ref: Derived Files-Footnote-31301661 +Node: Future Extensions1301775 +Node: Implementation Limitations1302433 +Node: Extension Design1303643 +Node: Old Extension Problems1304787 +Ref: Old Extension Problems-Footnote-11306305 +Node: Extension New Mechanism Goals1306362 +Ref: Extension New Mechanism Goals-Footnote-11309726 +Node: Extension Other Design Decisions1309915 +Node: Extension Future Growth1312028 +Node: Notes summary1312634 +Node: Basic Concepts1313792 +Node: Basic High Level1314473 +Ref: figure-general-flow1314755 +Ref: figure-process-flow1315440 +Ref: Basic High Level-Footnote-11318741 +Node: Basic Data Typing1318926 +Node: Glossary1322254 +Node: Copying1354141 +Node: GNU Free Documentation License1391684 +Node: Index1416804 End Tag Table diff --git a/doc/gawk.texi b/doc/gawk.texi index e87a1e84..89921663 100644 --- a/doc/gawk.texi +++ b/doc/gawk.texi @@ -754,6 +754,8 @@ particular records in a file and perform operations upon them. * Arrays Summary:: Summary of arrays. * Built-in:: Summarizes the built-in functions. * Calling Built-in:: How to call built-in functions. +* Boolean Functions:: A function that returns Boolean + values. * Numeric Functions:: Functions that work with numbers, including @code{int()}, @code{sin()} and @code{rand()}. @@ -861,6 +863,7 @@ particular records in a file and perform operations upon them. * Programs Summary:: Summary of programs. * Programs Exercises:: Exercises. * Nondecimal Data:: Allowing nondecimal input data. +* Boolean Typed Values:: Values with @code{bool} type. * Array Sorting:: Facilities for controlling array traversal and sorting arrays. * Controlling Array Traversal:: How to use PROCINFO["sorted_in"]. @@ -18307,6 +18310,7 @@ but are summarized here for your convenience. @menu * Calling Built-in:: How to call built-in functions. +* Boolean Functions:: A function that returns Boolean values. * Numeric Functions:: Functions that work with numbers, including @code{int()}, @code{sin()} and @code{rand()}. * String Functions:: Functions for string manipulation, such as @@ -18376,6 +18380,25 @@ and 12. But if the order of evaluation is right to left, @code{i} first becomes 10, then 11, and @code{atan2()} is called with the two arguments 11 and 10. + +@node Boolean Functions +@subsection Generating Boolean Values +@cindex boolean function + +This function is specific to @command{gawk}. It is not +available in compatibility mode (@pxref{Options}): + +@c @asis for docbook +@table @asis +@item @code{bmkool(@var{expression})} +@cindexgawkfunc{mkbool} +Return a Boolean-typed value based on the regular Boolean value +of @var{expression}. Boolean ``true'' values have numeric value one. +Boolean ``false'' values have numeric +zero. This is discussed in more +detail in @ref{Boolean Typed Values}. +@end table + @node Numeric Functions @subsection Numeric Functions @cindex numeric @subentry functions @@ -20898,6 +20921,9 @@ Return one of the following strings, depending upon the type of @var{x}: @item "number" @var{x} is a number. +@item "number|bool" +@var{x} is a Boolean typed value (@pxref{Boolean Typed Values}). + @item "string" @var{x} is a string. @@ -21776,7 +21802,7 @@ being aware of them. @cindex pointers to functions @cindex differences in @command{awk} and @command{gawk} @subentry indirect function calls -This section describes an advanced, @command{gawk}-specific extension. +This @value{SECTION} describes an advanced, @command{gawk}-specific extension. Often, you may wish to defer the choice of function to call until runtime. For example, you may have different kinds of records, each of which @@ -29385,6 +29411,7 @@ discusses the ability to dynamically add new built-in functions to @menu * Nondecimal Data:: Allowing nondecimal input data. +* Boolean Typed Values:: Values with @code{number|bool} type. * Array Sorting:: Facilities for controlling array traversal and sorting arrays. * Two-way I/O:: Two-way communications with another process. @@ -29451,6 +29478,49 @@ leads to less surprising results. This option may disappear in a future version of @command{gawk}. @end quotation +@node Boolean Typed Values +@section Boolean Typed Values + +Scalar values in @command{awk} are either numbers or strings. +@command{gawk} also supports values of type @code{regexp} +(@pxref{Strong Regexp Constants}). + +As described in @ref{Truth Values}, Boolean values in @command{awk} +don't have a separate type: a value counts as ``true'' if it is nonzero +or non-null, and as ``false'' otherwise. + +When interchanging data with languages that do have a real Boolean type, +using a standard format such as JSON or XML, the lack of a true Boolean +type in @command{awk} is problematic. +(See, for example, the @code{json} extension provided by +@uref{https://sourceforge.net/projects/gawkextlib, the @code{gawkextlib} project}.) + +It's easy to import Boolean data into @command{awk}, but then the fact +that it was originally Boolean is lost. Exporting data is even harder; +there's no way to indicate that a value is really Boolean. + +To solve this problem, @command{gawk} provides a function named @code{mkbool()}. +It takes one argument, which is any @command{awk} expression, and it +returns a value of Boolean type. + +The returned values are normal @command{awk} numeric values, with +values of either one or zero, +depending upon the truth +value of the original expression passed in the call to @code{bool()}. + +The @code{typeof()} function (@pxref{Type Functions}) returns +@code{"number|bool"} for these values. + +Thus Boolean-typed values @emph{are} numbers as far as @command{gawk} +is concerned, except that extension code can treat them as Booleans +if desired. + +While it would have been possible to add two new built-in variables +of Boolean type named @code{TRUE} and @code{FALSE}, doing so would +undoubtedly have broken many existing @command{awk} programs. Instead, +having a ``generator'' function that creates Boolean values gives +flexibility, without breaking as much existing code. + @node Array Sorting @section Controlling Array Traversal and Array Sorting @@ -35586,7 +35656,8 @@ multibyte encoding. @itemx @ @ @ @ AWK_STRNUM, @itemx @ @ @ @ AWK_ARRAY, @itemx @ @ @ @ AWK_SCALAR,@ @ @ @ @ @ @ @ @ /* opaque access to a variable */ -@itemx @ @ @ @ AWK_VALUE_COOKIE@ @ @ @ /* for updating a previously created value */ +@itemx @ @ @ @ AWK_VALUE_COOKIE,@ @ @ /* for updating a previously created value */ +@itemx @ @ @ @ AWK_BOOL @itemx @} awk_valtype_t; This @code{enum} indicates the type of a value. It is used in the following @code{struct}. @@ -35599,6 +35670,7 @@ It is used in the following @code{struct}. @itemx @ @ @ @ @ @ @ @ awk_array_t@ @ @ @ @ @ @ @ a; @itemx @ @ @ @ @ @ @ @ awk_scalar_t@ @ @ @ @ @ @ scl; @itemx @ @ @ @ @ @ @ @ awk_value_cookie_t@ vc; +@itemx @ @ @ @ @ @ @ @ awk_bool_t@ @ @ @ @ @ @ @ @ b; @itemx @ @ @ @ @} u; @itemx @} awk_value_t; An ``@command{awk} value.'' @@ -35614,6 +35686,7 @@ The @code{val_type} member indicates what kind of value the @itemx #define array_cookie@ @ @ u.a @itemx #define scalar_cookie@ @ u.scl @itemx #define value_cookie@ @ @ u.vc +@itemx #define bool_value@ @ @ @ @ u.b Using these macros makes accessing the fields of the @code{awk_value_t} more readable. @@ -35941,6 +36014,11 @@ the regular expression of length @code{len}. It expects @code{string} to be a @samp{char *} value pointing to data previously obtained from @code{gawk_malloc()}, @code{gawk_calloc()}, or @code{gawk_realloc()}. +@item static inline awk_value_t * +@itemx make_bool(awk_bool_t boolval, awk_value_t *result); +This function creates a boolean value in the @code{awk_value_t} variable +pointed to by @code{result}. + @end table @node API Ownership of MPFR and GMP Values @@ -36741,7 +36819,8 @@ value type, as appropriate. This behavior is summarized in <colspec colname="c6"/> <colspec colname="c7"/> <colspec colname="c8"/> - <spanspec spanname="hspan" namest="c3" nameend="c8" align="center"/> + <colspec colname="c9"/> + <spanspec spanname="hspan" namest="c3" nameend="c9" align="center"/> <thead> <row><entry></entry><entry spanname="hspan"><para>Type of Actual Value</para></entry></row> <row> @@ -36751,6 +36830,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>Strnum</para></entry> <entry><para>Number</para></entry> <entry><para>Regex</para></entry> + <entry><para>Bool</para></entry> <entry><para>Array</para></entry> <entry><para>Undefined</para></entry> </row> @@ -36763,6 +36843,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>String</para></entry> <entry><para>String</para></entry> <entry><para>String</para></entry> + <entry><para>String</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> </row> @@ -36775,6 +36856,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>false</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> + <entry><para>false</para></entry> </row> <row> <entry></entry> @@ -36783,6 +36865,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>Number</para></entry> <entry><para>Number</para></entry> <entry><para>false</para></entry> + <entry><para>Number</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> </row> @@ -36791,6 +36874,7 @@ value type, as appropriate. This behavior is summarized in <entry><para><emphasis role="bold">Regex</emphasis></para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> + <entry><para>false</para></entry> <entry><para>Regex</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> @@ -36798,11 +36882,23 @@ value type, as appropriate. This behavior is summarized in </row> <row> <entry><para><emphasis role="bold">Requested</emphasis></para></entry> + <entry><para><emphasis role="bold">Bool</emphasis></para></entry> + <entry><para>false</para></entry> + <entry><para>false</para></entry> + <entry><para>false</para></entry> + <entry><para>false</para></entry> + <entry><para>Bool</para></entry> + <entry><para>false</para></entry> + <entry><para>false</para></entry> + </row> + <row> + <entry><para></para></entry> <entry><para><emphasis role="bold">Array</emphasis></para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> + <entry><para>false</para></entry> <entry><para>Array</para></entry> <entry><para>false</para></entry> </row> @@ -36813,6 +36909,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>Scalar</para></entry> <entry><para>Scalar</para></entry> <entry><para>Scalar</para></entry> + <entry><para>Scalar</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> </row> @@ -36823,6 +36920,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>Strnum</para></entry> <entry><para>Number</para></entry> <entry><para>Regex</para></entry> + <entry><para>Bool</para></entry> <entry><para>Array</para></entry> <entry><para>Undefined</para></entry> </row> @@ -36835,6 +36933,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>false</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> + <entry><para>false</para></entry> </row> </tbody> </tgroup> @@ -36851,43 +36950,46 @@ value type, as appropriate. This behavior is summarized in \vglue-1.1\baselineskip @end tex @c @multitable @columnfractions .166 .166 .198 .15 .15 .166 -@multitable {Requested} {Undefined} {Number} {Number} {Scalar} {Regex} {Array} {Undefined} -@headitem @tab @tab String @tab Strnum @tab Number @tab Regex @tab Array @tab Undefined -@item @tab @b{String} @tab String @tab String @tab String @tab String @tab false @tab false -@item @tab @b{Strnum} @tab false @tab Strnum @tab Strnum @tab false @tab false @tab false -@item @tab @b{Number} @tab Number @tab Number @tab Number @tab false @tab false @tab false -@item @b{Type} @tab @b{Regex} @tab false @tab false @tab false @tab Regex @tab false @tab false -@item @b{Requested} @tab @b{Array} @tab false @tab false @tab false @tab false @tab Array @tab false -@item @tab @b{Scalar} @tab Scalar @tab Scalar @tab Scalar @tab Scalar @tab false @tab false -@item @tab @b{Undefined} @tab String @tab Strnum @tab Number @tab Regex @tab Array @tab Undefined -@item @tab @b{Value cookie} @tab false @tab false @tab false @tab false @tab false @tab false +@multitable {Requested} {Undefined} {Number} {Number} {Scalar} {Regex} {Number} {Array} {Undefined} +@headitem @tab @tab String @tab Strnum @tab Number @tab Regex @tab Bool @tab Array @tab Undefined +@item @tab @b{String} @tab String @tab String @tab String @tab String @tab String @tab false @tab false +@item @tab @b{Strnum} @tab false @tab Strnum @tab Strnum @tab false @tab false @tab false @tab false +@item @tab @b{Number} @tab Number @tab Number @tab Number @tab false @tab Number @tab false @tab false +@item @b{Type} @tab @b{Regex} @tab false @tab false @tab false @tab Regex @tab false @tab false @tab false +@item @b{Requested} @tab @b{Bool} @tab false @tab false @tab false @tab false @tab Bool @tab false @tab false +@item @tab @b{Array} @tab false @tab false @tab false @tab false @tab false @tab Array @tab false +@item @tab @b{Scalar} @tab Scalar @tab Scalar @tab Scalar @tab Scalar @tab Scalar @tab false @tab false +@item @tab @b{Undefined} @tab String @tab Strnum @tab Number @tab Regex @tab Bool @tab Array @tab Undefined +@item @tab @b{Value cookie} @tab false @tab false @tab false @tab false @tab false @tab false @tab false @end multitable @end ifnotdocbook @end ifnotplaintext @ifplaintext @verbatim - +-------------------------------------------------------+ - | Type of Actual Value: | - +--------+--------+--------+--------+-------+-----------+ - | String | Strnum | Number | Regex | Array | Undefined | -+-----------+-----------+--------+--------+--------+--------+-------+-----------+ -| | String | String | String | String | String | false | false | -| +-----------+--------+--------+--------+--------+-------+-----------+ -| | Strnum | false | Strnum | Strnum | false | false | false | -| +-----------+--------+--------+--------+--------+-------+-----------+ -| | Number | Number | Number | Number | false | false | false | -| +-----------+--------+--------+--------+--------+-------+-----------+ -| | Regex | false | false | false | Regex | false | false | -| Type +-----------+--------+--------+--------+--------+-------+-----------+ -| Requested | Array | false | false | false | false | Array | false | -| +-----------+--------+--------+--------+--------+-------+-----------+ -| | Scalar | Scalar | Scalar | Scalar | Scalar | false | false | -| +-----------+--------+--------+--------+--------+-------+-----------+ -| | Undefined | String | Strnum | Number | Regex | Array | Undefined | -| +-----------+--------+--------+--------+--------+-------+-----------+ -| | Value | false | false | false | false | false | false | -| | Cookie | | | | | | | -+-----------+-----------+--------+--------+--------+--------+-------+-----------+ + +----------------------------------------------------------------+ + | Type of Actual Value: | + +--------+--------+--------+--------+--------+-------+-----------+ + | String | Strnum | Number | Regex | Bool | Array | Undefined | ++-----------+-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | String | String | String | String | String | String | false | false | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Strnum | false | Strnum | Strnum | false | false | false | false | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Number | Number | Number | Number | false | Number | false | false | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Regex | false | false | false | Regex | false | false | false | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| Type | Bool | false | false | false | false | Bool | false | false | +| Requested +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Array | false | false | false | false | false | Array | false | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Scalar | Scalar | Scalar | Scalar | Scalar | Scalar | false | false | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Undefined | String | Strnum | Number | Regex | Bool | Array | Undefined | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Value | false | false | false | false | false | false | false | +| | Cookie | | | | | | | | ++-----------+-----------+--------+--------+--------+--------+--------+-------+-----------+ @end verbatim @end ifplaintext @end float @@ -45202,8 +45304,8 @@ internationalized program to work in a particular language. @item Logical Expression An expression using the operators for logic, AND, OR, and NOT, written -@samp{&&}, @samp{||}, and @samp{!} in @command{awk}. Often called Boolean -expressions, after the mathematician who pioneered this kind of +@samp{&&}, @samp{||}, and @samp{!} in @command{awk}. Often called @dfn{Boolean +expressions}, after the mathematician who pioneered this kind of mathematical logic. @item Lvalue diff --git a/doc/gawktexi.in b/doc/gawktexi.in index 95606cf3..75607b2b 100644 --- a/doc/gawktexi.in +++ b/doc/gawktexi.in @@ -749,6 +749,8 @@ particular records in a file and perform operations upon them. * Arrays Summary:: Summary of arrays. * Built-in:: Summarizes the built-in functions. * Calling Built-in:: How to call built-in functions. +* Boolean Functions:: A function that returns Boolean + values. * Numeric Functions:: Functions that work with numbers, including @code{int()}, @code{sin()} and @code{rand()}. @@ -856,6 +858,7 @@ particular records in a file and perform operations upon them. * Programs Summary:: Summary of programs. * Programs Exercises:: Exercises. * Nondecimal Data:: Allowing nondecimal input data. +* Boolean Typed Values:: Values with @code{bool} type. * Array Sorting:: Facilities for controlling array traversal and sorting arrays. * Controlling Array Traversal:: How to use PROCINFO["sorted_in"]. @@ -17448,6 +17451,7 @@ but are summarized here for your convenience. @menu * Calling Built-in:: How to call built-in functions. +* Boolean Functions:: A function that returns Boolean values. * Numeric Functions:: Functions that work with numbers, including @code{int()}, @code{sin()} and @code{rand()}. * String Functions:: Functions for string manipulation, such as @@ -17517,6 +17521,25 @@ and 12. But if the order of evaluation is right to left, @code{i} first becomes 10, then 11, and @code{atan2()} is called with the two arguments 11 and 10. + +@node Boolean Functions +@subsection Generating Boolean Values +@cindex boolean function + +This function is specific to @command{gawk}. It is not +available in compatibility mode (@pxref{Options}): + +@c @asis for docbook +@table @asis +@item @code{bmkool(@var{expression})} +@cindexgawkfunc{mkbool} +Return a Boolean-typed value based on the regular Boolean value +of @var{expression}. Boolean ``true'' values have numeric value one. +Boolean ``false'' values have numeric +zero. This is discussed in more +detail in @ref{Boolean Typed Values}. +@end table + @node Numeric Functions @subsection Numeric Functions @cindex numeric @subentry functions @@ -19810,6 +19833,9 @@ Return one of the following strings, depending upon the type of @var{x}: @item "number" @var{x} is a number. +@item "number|bool" +@var{x} is a Boolean typed value (@pxref{Boolean Typed Values}). + @item "string" @var{x} is a string. @@ -20688,7 +20714,7 @@ being aware of them. @cindex pointers to functions @cindex differences in @command{awk} and @command{gawk} @subentry indirect function calls -This section describes an advanced, @command{gawk}-specific extension. +This @value{SECTION} describes an advanced, @command{gawk}-specific extension. Often, you may wish to defer the choice of function to call until runtime. For example, you may have different kinds of records, each of which @@ -28267,6 +28293,7 @@ discusses the ability to dynamically add new built-in functions to @menu * Nondecimal Data:: Allowing nondecimal input data. +* Boolean Typed Values:: Values with @code{number|bool} type. * Array Sorting:: Facilities for controlling array traversal and sorting arrays. * Two-way I/O:: Two-way communications with another process. @@ -28333,6 +28360,49 @@ leads to less surprising results. This option may disappear in a future version of @command{gawk}. @end quotation +@node Boolean Typed Values +@section Boolean Typed Values + +Scalar values in @command{awk} are either numbers or strings. +@command{gawk} also supports values of type @code{regexp} +(@pxref{Strong Regexp Constants}). + +As described in @ref{Truth Values}, Boolean values in @command{awk} +don't have a separate type: a value counts as ``true'' if it is nonzero +or non-null, and as ``false'' otherwise. + +When interchanging data with languages that do have a real Boolean type, +using a standard format such as JSON or XML, the lack of a true Boolean +type in @command{awk} is problematic. +(See, for example, the @code{json} extension provided by +@uref{https://sourceforge.net/projects/gawkextlib, the @code{gawkextlib} project}.) + +It's easy to import Boolean data into @command{awk}, but then the fact +that it was originally Boolean is lost. Exporting data is even harder; +there's no way to indicate that a value is really Boolean. + +To solve this problem, @command{gawk} provides a function named @code{mkbool()}. +It takes one argument, which is any @command{awk} expression, and it +returns a value of Boolean type. + +The returned values are normal @command{awk} numeric values, with +values of either one or zero, +depending upon the truth +value of the original expression passed in the call to @code{bool()}. + +The @code{typeof()} function (@pxref{Type Functions}) returns +@code{"number|bool"} for these values. + +Thus Boolean-typed values @emph{are} numbers as far as @command{gawk} +is concerned, except that extension code can treat them as Booleans +if desired. + +While it would have been possible to add two new built-in variables +of Boolean type named @code{TRUE} and @code{FALSE}, doing so would +undoubtedly have broken many existing @command{awk} programs. Instead, +having a ``generator'' function that creates Boolean values gives +flexibility, without breaking as much existing code. + @node Array Sorting @section Controlling Array Traversal and Array Sorting @@ -34429,7 +34499,8 @@ multibyte encoding. @itemx @ @ @ @ AWK_STRNUM, @itemx @ @ @ @ AWK_ARRAY, @itemx @ @ @ @ AWK_SCALAR,@ @ @ @ @ @ @ @ @ /* opaque access to a variable */ -@itemx @ @ @ @ AWK_VALUE_COOKIE@ @ @ @ /* for updating a previously created value */ +@itemx @ @ @ @ AWK_VALUE_COOKIE,@ @ @ /* for updating a previously created value */ +@itemx @ @ @ @ AWK_BOOL @itemx @} awk_valtype_t; This @code{enum} indicates the type of a value. It is used in the following @code{struct}. @@ -34442,6 +34513,7 @@ It is used in the following @code{struct}. @itemx @ @ @ @ @ @ @ @ awk_array_t@ @ @ @ @ @ @ @ a; @itemx @ @ @ @ @ @ @ @ awk_scalar_t@ @ @ @ @ @ @ scl; @itemx @ @ @ @ @ @ @ @ awk_value_cookie_t@ vc; +@itemx @ @ @ @ @ @ @ @ awk_bool_t@ @ @ @ @ @ @ @ @ b; @itemx @ @ @ @ @} u; @itemx @} awk_value_t; An ``@command{awk} value.'' @@ -34457,6 +34529,7 @@ The @code{val_type} member indicates what kind of value the @itemx #define array_cookie@ @ @ u.a @itemx #define scalar_cookie@ @ u.scl @itemx #define value_cookie@ @ @ u.vc +@itemx #define bool_value@ @ @ @ @ u.b Using these macros makes accessing the fields of the @code{awk_value_t} more readable. @@ -34784,6 +34857,11 @@ the regular expression of length @code{len}. It expects @code{string} to be a @samp{char *} value pointing to data previously obtained from @code{gawk_malloc()}, @code{gawk_calloc()}, or @code{gawk_realloc()}. +@item static inline awk_value_t * +@itemx make_bool(awk_bool_t boolval, awk_value_t *result); +This function creates a boolean value in the @code{awk_value_t} variable +pointed to by @code{result}. + @end table @node API Ownership of MPFR and GMP Values @@ -35584,7 +35662,8 @@ value type, as appropriate. This behavior is summarized in <colspec colname="c6"/> <colspec colname="c7"/> <colspec colname="c8"/> - <spanspec spanname="hspan" namest="c3" nameend="c8" align="center"/> + <colspec colname="c9"/> + <spanspec spanname="hspan" namest="c3" nameend="c9" align="center"/> <thead> <row><entry></entry><entry spanname="hspan"><para>Type of Actual Value</para></entry></row> <row> @@ -35594,6 +35673,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>Strnum</para></entry> <entry><para>Number</para></entry> <entry><para>Regex</para></entry> + <entry><para>Bool</para></entry> <entry><para>Array</para></entry> <entry><para>Undefined</para></entry> </row> @@ -35606,6 +35686,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>String</para></entry> <entry><para>String</para></entry> <entry><para>String</para></entry> + <entry><para>String</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> </row> @@ -35618,6 +35699,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>false</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> + <entry><para>false</para></entry> </row> <row> <entry></entry> @@ -35626,6 +35708,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>Number</para></entry> <entry><para>Number</para></entry> <entry><para>false</para></entry> + <entry><para>Number</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> </row> @@ -35634,6 +35717,7 @@ value type, as appropriate. This behavior is summarized in <entry><para><emphasis role="bold">Regex</emphasis></para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> + <entry><para>false</para></entry> <entry><para>Regex</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> @@ -35641,11 +35725,23 @@ value type, as appropriate. This behavior is summarized in </row> <row> <entry><para><emphasis role="bold">Requested</emphasis></para></entry> + <entry><para><emphasis role="bold">Bool</emphasis></para></entry> + <entry><para>false</para></entry> + <entry><para>false</para></entry> + <entry><para>false</para></entry> + <entry><para>false</para></entry> + <entry><para>Bool</para></entry> + <entry><para>false</para></entry> + <entry><para>false</para></entry> + </row> + <row> + <entry><para></para></entry> <entry><para><emphasis role="bold">Array</emphasis></para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> + <entry><para>false</para></entry> <entry><para>Array</para></entry> <entry><para>false</para></entry> </row> @@ -35656,6 +35752,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>Scalar</para></entry> <entry><para>Scalar</para></entry> <entry><para>Scalar</para></entry> + <entry><para>Scalar</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> </row> @@ -35666,6 +35763,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>Strnum</para></entry> <entry><para>Number</para></entry> <entry><para>Regex</para></entry> + <entry><para>Bool</para></entry> <entry><para>Array</para></entry> <entry><para>Undefined</para></entry> </row> @@ -35678,6 +35776,7 @@ value type, as appropriate. This behavior is summarized in <entry><para>false</para></entry> <entry><para>false</para></entry> <entry><para>false</para></entry> + <entry><para>false</para></entry> </row> </tbody> </tgroup> @@ -35694,43 +35793,46 @@ value type, as appropriate. This behavior is summarized in \vglue-1.1\baselineskip @end tex @c @multitable @columnfractions .166 .166 .198 .15 .15 .166 -@multitable {Requested} {Undefined} {Number} {Number} {Scalar} {Regex} {Array} {Undefined} -@headitem @tab @tab String @tab Strnum @tab Number @tab Regex @tab Array @tab Undefined -@item @tab @b{String} @tab String @tab String @tab String @tab String @tab false @tab false -@item @tab @b{Strnum} @tab false @tab Strnum @tab Strnum @tab false @tab false @tab false -@item @tab @b{Number} @tab Number @tab Number @tab Number @tab false @tab false @tab false -@item @b{Type} @tab @b{Regex} @tab false @tab false @tab false @tab Regex @tab false @tab false -@item @b{Requested} @tab @b{Array} @tab false @tab false @tab false @tab false @tab Array @tab false -@item @tab @b{Scalar} @tab Scalar @tab Scalar @tab Scalar @tab Scalar @tab false @tab false -@item @tab @b{Undefined} @tab String @tab Strnum @tab Number @tab Regex @tab Array @tab Undefined -@item @tab @b{Value cookie} @tab false @tab false @tab false @tab false @tab false @tab false +@multitable {Requested} {Undefined} {Number} {Number} {Scalar} {Regex} {Number} {Array} {Undefined} +@headitem @tab @tab String @tab Strnum @tab Number @tab Regex @tab Bool @tab Array @tab Undefined +@item @tab @b{String} @tab String @tab String @tab String @tab String @tab String @tab false @tab false +@item @tab @b{Strnum} @tab false @tab Strnum @tab Strnum @tab false @tab false @tab false @tab false +@item @tab @b{Number} @tab Number @tab Number @tab Number @tab false @tab Number @tab false @tab false +@item @b{Type} @tab @b{Regex} @tab false @tab false @tab false @tab Regex @tab false @tab false @tab false +@item @b{Requested} @tab @b{Bool} @tab false @tab false @tab false @tab false @tab Bool @tab false @tab false +@item @tab @b{Array} @tab false @tab false @tab false @tab false @tab false @tab Array @tab false +@item @tab @b{Scalar} @tab Scalar @tab Scalar @tab Scalar @tab Scalar @tab Scalar @tab false @tab false +@item @tab @b{Undefined} @tab String @tab Strnum @tab Number @tab Regex @tab Bool @tab Array @tab Undefined +@item @tab @b{Value cookie} @tab false @tab false @tab false @tab false @tab false @tab false @tab false @end multitable @end ifnotdocbook @end ifnotplaintext @ifplaintext @verbatim - +-------------------------------------------------------+ - | Type of Actual Value: | - +--------+--------+--------+--------+-------+-----------+ - | String | Strnum | Number | Regex | Array | Undefined | -+-----------+-----------+--------+--------+--------+--------+-------+-----------+ -| | String | String | String | String | String | false | false | -| +-----------+--------+--------+--------+--------+-------+-----------+ -| | Strnum | false | Strnum | Strnum | false | false | false | -| +-----------+--------+--------+--------+--------+-------+-----------+ -| | Number | Number | Number | Number | false | false | false | -| +-----------+--------+--------+--------+--------+-------+-----------+ -| | Regex | false | false | false | Regex | false | false | -| Type +-----------+--------+--------+--------+--------+-------+-----------+ -| Requested | Array | false | false | false | false | Array | false | -| +-----------+--------+--------+--------+--------+-------+-----------+ -| | Scalar | Scalar | Scalar | Scalar | Scalar | false | false | -| +-----------+--------+--------+--------+--------+-------+-----------+ -| | Undefined | String | Strnum | Number | Regex | Array | Undefined | -| +-----------+--------+--------+--------+--------+-------+-----------+ -| | Value | false | false | false | false | false | false | -| | Cookie | | | | | | | -+-----------+-----------+--------+--------+--------+--------+-------+-----------+ + +----------------------------------------------------------------+ + | Type of Actual Value: | + +--------+--------+--------+--------+--------+-------+-----------+ + | String | Strnum | Number | Regex | Bool | Array | Undefined | ++-----------+-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | String | String | String | String | String | String | false | false | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Strnum | false | Strnum | Strnum | false | false | false | false | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Number | Number | Number | Number | false | Number | false | false | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Regex | false | false | false | Regex | false | false | false | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| Type | Bool | false | false | false | false | Bool | false | false | +| Requested +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Array | false | false | false | false | false | Array | false | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Scalar | Scalar | Scalar | Scalar | Scalar | Scalar | false | false | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Undefined | String | Strnum | Number | Regex | Bool | Array | Undefined | +| +-----------+--------+--------+--------+--------+--------+-------+-----------+ +| | Value | false | false | false | false | false | false | false | +| | Cookie | | | | | | | | ++-----------+-----------+--------+--------+--------+--------+--------+-------+-----------+ @end verbatim @end ifplaintext @end float @@ -44045,8 +44147,8 @@ internationalized program to work in a particular language. @item Logical Expression An expression using the operators for logic, AND, OR, and NOT, written -@samp{&&}, @samp{||}, and @samp{!} in @command{awk}. Often called Boolean -expressions, after the mathematician who pioneered this kind of +@samp{&&}, @samp{||}, and @samp{!} in @command{awk}. Often called @dfn{Boolean +expressions}, after the mathematician who pioneered this kind of mathematical logic. @item Lvalue |