Version 91.txr-91

5 files changed, 200 insertions, 122 deletions

diff --git a/RELNOTES b/RELNOTES
index 42af9ff0..b9a87697 100644
--- a/RELNOTES
+++ b/RELNOTES
@@ -1,3 +1,77 @@
+                                     TXR 91
+                                   2014-07-02
+
+
+
+  Features
+
+  - @(load `@stdlib/ver`) brings in a definition of a new variable
+    called *lib-version* which lets programs check what version of
+    the library they are using.
+
+  - New functions where and sel for working with multiple indexes
+    into a sequence.
+
+  - New function seqp for testing whether an object is a sequence of any type.
+
+  - New functions pos-max, pos-min, find-max and find-min.
+
+  - New character constant #\pnul denoting the U+DC00 code
+    (TXR's  "pseudo null").
+
+  - New function tuples for reorganizing a sequence into tuples.
+
+  - New functions true and false, expressive in applicative programming:
+    for instance [all true list].
+
+  - New functions member and member-if.
+
+  - New function multi for applying a one-sequence operation to
+    parallel sequences.
+
+  - New functions tf, nilf, retf, apf, ipf.
+
+  - New macros ret, ip and ap.
+
+  - New function iapply for applying improper lists.
+
+  - New functions transpose and zip.
+
+  - New functions tok-where and range-regex.
+
+  - New function bit for testing bits.
+
+  - [] indexing now allows element extraction by index list,
+    as well as assignment by index list, increasing the "slicing power".
+
+  Bugs
+
+  - Fixed reliance on leading slash as indicator of absolute path in @(load).
+
+  - Fixed breakage in range and range* function (regression introduced
+    in TXR 89).
+
+  - Fixed bug in dwim operator: Lisp-1 evaluation semantics being propagated
+    into nested forms, contrary to documentation.
+
+  - Line number of error correctly reported in some situations in which
+    it previously wasn't.
+
+  - Fixed macros not being expanded inside quasiliteral brace notation.
+
+  - Fixed broken last function.
+
+  - Fixed broken bignum bit operations, not handling negative values
+    properly.
+
+  - Fixed reversed logic of logtest function.
+
+  - Fixed some memory leaks in MPI bignum integer operations.
+
+  - Documentation fixes.
+
+
+
                                      TXR 90
                                    2014-06-11
 
diff --git a/configure b/configure
index f57a81da..f61af1e1 100755
--- a/configure
+++ b/configure
@@ -407,7 +407,7 @@ fi
 #
 
 
-txr_ver=90
+txr_ver=91
 
 #
 # The all important banner.
diff --git a/dep.mk b/dep.mk
index a403369b..65612db8 100644
--- a/dep.mk
+++ b/dep.mk
@@ -1,4 +1,4 @@
-./txr.o: config.h $(top_srcdir)/./lib.h $(top_srcdir)/./stream.h $(top_srcdir)/./gc.h $(top_srcdir)/./signal.h $(top_srcdir)/./unwind.h $(top_srcdir)/./parser.h $(top_srcdir)/./match.h $(top_srcdir)/./utf8.h $(top_srcdir)/./debug.h $(top_srcdir)/./syslog.h $(top_srcdir)/./eval.h $(top_srcdir)/./regex.h $(top_srcdir)/./txr.h
+./txr.o: config.h $(top_srcdir)/./lib.h $(top_srcdir)/./stream.h $(top_srcdir)/./gc.h $(top_srcdir)/./signal.h $(top_srcdir)/./unwind.h $(top_srcdir)/./parser.h $(top_srcdir)/./match.h $(top_srcdir)/./utf8.h $(top_srcdir)/./debug.h $(top_srcdir)/./syslog.h $(top_srcdir)/./eval.h $(top_srcdir)/./regex.h $(top_srcdir)/./arith.h $(top_srcdir)/./txr.h
 ./lex.yy.o: config.h $(top_srcdir)/./lib.h y.tab.h $(top_srcdir)/./gc.h $(top_srcdir)/./stream.h $(top_srcdir)/./utf8.h $(top_srcdir)/./signal.h $(top_srcdir)/./unwind.h $(top_srcdir)/./hash.h $(top_srcdir)/./parser.h
 ./y.tab.o: config.h $(top_srcdir)/./lib.h $(top_srcdir)/./signal.h $(top_srcdir)/./unwind.h $(top_srcdir)/./regex.h $(top_srcdir)/./utf8.h $(top_srcdir)/./match.h $(top_srcdir)/./hash.h $(top_srcdir)/./eval.h $(top_srcdir)/./stream.h $(top_srcdir)/./parser.h
 ./match.o: config.h $(top_srcdir)/./lib.h $(top_srcdir)/./gc.h $(top_srcdir)/./signal.h $(top_srcdir)/./unwind.h $(top_srcdir)/./regex.h $(top_srcdir)/./stream.h $(top_srcdir)/./parser.h $(top_srcdir)/./txr.h $(top_srcdir)/./utf8.h $(top_srcdir)/./filter.h $(top_srcdir)/./hash.h $(top_srcdir)/./debug.h $(top_srcdir)/./eval.h $(top_srcdir)/./match.h
diff --git a/txr.1 b/txr.1
index 801c5f5f..4b02da10 100644
--- a/txr.1
+++ b/txr.1
@@ -21,9 +21,9 @@
 .\"IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 .\"WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 
-.TH "TXR" 1 2014-06-11 "Utility Commands" "TXR Text Processing Language" "Kaz Kylheku"
+.TH "TXR" 1 2014-07-02 "Utility Commands" "TXR Text Processing Language" "Kaz Kylheku"
 .SH NAME
-txr \- text processing language (version 90)
+txr \- text processing language (version 91)
 .SH SYNOPSIS
 .B txr [ options ] query-file { data-file }*
 .sp
diff --git a/txr.vim b/txr.vim
index 5e9c9b62..5e694160 100644
--- a/txr.vim
+++ b/txr.vim
@@ -42,77 +42,79 @@ syn keyword txl_keyword contained - / /= <
 syn keyword txl_keyword contained <= = > >=
 syn keyword txl_keyword contained abs abs-path-p acons acons-new
 syn keyword txl_keyword contained aconsql-new acos alist-nremove alist-remove
-syn keyword txl_keyword contained all and andf append
-syn keyword txl_keyword contained append* append-each append-each* apply
-syn keyword txl_keyword contained ash asin assoc assql
-syn keyword txl_keyword contained atan atan2 atom bignump
-syn keyword txl_keyword contained block boundp break-str call
-syn keyword txl_keyword contained car cat-str cat-vec catch
-syn keyword txl_keyword contained cdr ceil chain chdir
-syn keyword txl_keyword contained chr-isalnum chr-isalpha chr-isascii chr-iscntrl
-syn keyword txl_keyword contained chr-isdigit chr-isgraph chr-islower chr-isprint
-syn keyword txl_keyword contained chr-ispunct chr-isspace chr-isupper chr-isxdigit
-syn keyword txl_keyword contained chr-num chr-str chr-str-set chr-tolower
-syn keyword txl_keyword contained chr-toupper chrp close-stream closelog
-syn keyword txl_keyword contained cmp-str collect-each collect-each* comb
-syn keyword txl_keyword contained compl-span-str cond cons conses
-syn keyword txl_keyword contained conses* consp copy copy-alist
-syn keyword txl_keyword contained copy-cons copy-hash copy-list copy-str
-syn keyword txl_keyword contained copy-vec cos count-if countq
-syn keyword txl_keyword contained countql countqual cum-norm-dist daemon
-syn keyword txl_keyword contained dec defmacro defsymacro defun
-syn keyword txl_keyword contained defvar del delay delete-package
-syn keyword txl_keyword contained do dohash downcase-str dwim
-syn keyword txl_keyword contained each each* empty env
-syn keyword txl_keyword contained env-fbind env-hash env-vbind eq
-syn keyword txl_keyword contained eql equal errno error
-syn keyword txl_keyword contained eval evenp exit exp
-syn keyword txl_keyword contained expt exptmod false fboundp
-syn keyword txl_keyword contained fifth filter-equal filter-string-tree find
-syn keyword txl_keyword contained find-if find-max find-min find-package
-syn keyword txl_keyword contained first fixnump flatten flatten*
-syn keyword txl_keyword contained flip flo-int flo-str floatp
-syn keyword txl_keyword contained floor flush-stream for for*
-syn keyword txl_keyword contained force format fourth fun
-syn keyword txl_keyword contained func-get-env func-get-form func-set-env functionp
-syn keyword txl_keyword contained gcd gen generate gensym
-syn keyword txl_keyword contained get-byte get-char get-hash-userdata get-line
-syn keyword txl_keyword contained get-list-from-stream get-sig-handler get-string-from-stream gethash
-syn keyword txl_keyword contained group-by gun hash hash-alist
-syn keyword txl_keyword contained hash-construct hash-count hash-diff hash-eql
-syn keyword txl_keyword contained hash-equal hash-isec hash-keys hash-pairs
-syn keyword txl_keyword contained hash-uni hash-update hash-update-1 hash-values
-syn keyword txl_keyword contained hashp html-decode html-encode identity
+syn keyword txl_keyword contained all and andf ap
+syn keyword txl_keyword contained apf append append* append-each
+syn keyword txl_keyword contained append-each* apply ash asin
+syn keyword txl_keyword contained assoc assql atan atan2
+syn keyword txl_keyword contained atom bignump bit block
+syn keyword txl_keyword contained boundp break-str call car
+syn keyword txl_keyword contained cat-str cat-vec catch cdr
+syn keyword txl_keyword contained ceil chain chdir chr-isalnum
+syn keyword txl_keyword contained chr-isalpha chr-isascii chr-iscntrl chr-isdigit
+syn keyword txl_keyword contained chr-isgraph chr-islower chr-isprint chr-ispunct
+syn keyword txl_keyword contained chr-isspace chr-isupper chr-isxdigit chr-num
+syn keyword txl_keyword contained chr-str chr-str-set chr-tolower chr-toupper
+syn keyword txl_keyword contained chrp close-stream closelog cmp-str
+syn keyword txl_keyword contained collect-each collect-each* comb compl-span-str
+syn keyword txl_keyword contained cond cons conses conses*
+syn keyword txl_keyword contained consp copy copy-alist copy-cons
+syn keyword txl_keyword contained copy-hash copy-list copy-str copy-vec
+syn keyword txl_keyword contained cos count-if countq countql
+syn keyword txl_keyword contained countqual cum-norm-dist daemon dec
+syn keyword txl_keyword contained defmacro defsymacro defun defvar
+syn keyword txl_keyword contained del delay delete-package do
+syn keyword txl_keyword contained dohash downcase-str dwim each
+syn keyword txl_keyword contained each* empty env env-fbind
+syn keyword txl_keyword contained env-hash env-vbind eq eql
+syn keyword txl_keyword contained equal errno error eval
+syn keyword txl_keyword contained evenp exit exp expt
+syn keyword txl_keyword contained exptmod false fboundp fifth
+syn keyword txl_keyword contained filter-equal filter-string-tree find find-if
+syn keyword txl_keyword contained find-max find-min find-package first
+syn keyword txl_keyword contained fixnump flatten flatten* flip
+syn keyword txl_keyword contained flo-int flo-str floatp floor
+syn keyword txl_keyword contained flush-stream for for* force
+syn keyword txl_keyword contained format fourth fun func-get-env
+syn keyword txl_keyword contained func-get-form func-set-env functionp gcd
+syn keyword txl_keyword contained gen generate gensym get-byte
+syn keyword txl_keyword contained get-char get-hash-userdata get-line get-list-from-stream
+syn keyword txl_keyword contained get-sig-handler get-string-from-stream gethash group-by
+syn keyword txl_keyword contained gun hash hash-alist hash-construct
+syn keyword txl_keyword contained hash-count hash-diff hash-eql hash-equal
+syn keyword txl_keyword contained hash-isec hash-keys hash-pairs hash-uni
+syn keyword txl_keyword contained hash-update hash-update-1 hash-values hashp
+syn keyword txl_keyword contained html-decode html-encode iapply identity
 syn keyword txl_keyword contained if iff iffi inc
 syn keyword txl_keyword contained inhash int-flo int-str integerp
-syn keyword txl_keyword contained intern interp-fun-p isqrt keep-if
-syn keyword txl_keyword contained keep-if* keywordp lambda last
-syn keyword txl_keyword contained lazy-str lazy-str-force lazy-str-force-upto lazy-str-get-trailing-list
-syn keyword txl_keyword contained lazy-stream-cons lazy-stringp lcons-fun ldiff
-syn keyword txl_keyword contained length length-list length-str length-str-<
-syn keyword txl_keyword contained length-str-<= length-str-> length-str->= length-vec
-syn keyword txl_keyword contained let let* link lisp-parse
-syn keyword txl_keyword contained list list* list-str list-vector
-syn keyword txl_keyword contained listp log log-alert log-auth
-syn keyword txl_keyword contained log-authpriv log-cons log-crit log-daemon
-syn keyword txl_keyword contained log-debug log-emerg log-err log-info
-syn keyword txl_keyword contained log-ndelay log-notice log-nowait log-odelay
-syn keyword txl_keyword contained log-perror log-pid log-user log-warning
-syn keyword txl_keyword contained log10 logand logior lognot
-syn keyword txl_keyword contained logtest logtrunc logxor macro-form-p
-syn keyword txl_keyword contained macro-time macroexpand macroexpand-1 macrolet
-syn keyword txl_keyword contained major make-catenated-stream make-env make-hash
-syn keyword txl_keyword contained make-lazy-cons make-like make-package make-random-state
-syn keyword txl_keyword contained make-similar-hash make-string-byte-input-stream make-string-input-stream make-string-output-stream
-syn keyword txl_keyword contained make-strlist-output-stream make-sym make-time make-time-utc
-syn keyword txl_keyword contained make-trie makedev mapcar mapcar*
-syn keyword txl_keyword contained maphash mappend mappend* mask
-syn keyword txl_keyword contained match-fun match-regex match-regex-right match-str
-syn keyword txl_keyword contained match-str-tree max member member-if
-syn keyword txl_keyword contained memq memql memqual merge
-syn keyword txl_keyword contained min minor mkdir mknod
-syn keyword txl_keyword contained mkstring mod multi-sort n-choose-k
-syn keyword txl_keyword contained n-perm-k none not nreverse
+syn keyword txl_keyword contained intern interp-fun-p ip ipf
+syn keyword txl_keyword contained isqrt keep-if keep-if* keywordp
+syn keyword txl_keyword contained lambda last lazy-str lazy-str-force
+syn keyword txl_keyword contained lazy-str-force-upto lazy-str-get-trailing-list lazy-stream-cons lazy-stringp
+syn keyword txl_keyword contained lcons-fun ldiff length length-list
+syn keyword txl_keyword contained length-str length-str-< length-str-<= length-str->
+syn keyword txl_keyword contained length-str->= length-vec let let*
+syn keyword txl_keyword contained link lisp-parse list list*
+syn keyword txl_keyword contained list-str list-vector listp log
+syn keyword txl_keyword contained log-alert log-auth log-authpriv log-cons
+syn keyword txl_keyword contained log-crit log-daemon log-debug log-emerg
+syn keyword txl_keyword contained log-err log-info log-ndelay log-notice
+syn keyword txl_keyword contained log-nowait log-odelay log-perror log-pid
+syn keyword txl_keyword contained log-user log-warning log10 logand
+syn keyword txl_keyword contained logior lognot logtest logtrunc
+syn keyword txl_keyword contained logxor macro-form-p macro-time macroexpand
+syn keyword txl_keyword contained macroexpand-1 macrolet major make-catenated-stream
+syn keyword txl_keyword contained make-env make-hash make-lazy-cons make-like
+syn keyword txl_keyword contained make-package make-random-state make-similar-hash make-string-byte-input-stream
+syn keyword txl_keyword contained make-string-input-stream make-string-output-stream make-strlist-output-stream make-sym
+syn keyword txl_keyword contained make-time make-time-utc make-trie makedev
+syn keyword txl_keyword contained mapcar mapcar* maphash mappend
+syn keyword txl_keyword contained mappend* mask match-fun match-regex
+syn keyword txl_keyword contained match-regex-right match-str match-str-tree max
+syn keyword txl_keyword contained member member-if memq memql
+syn keyword txl_keyword contained memqual merge min minor
+syn keyword txl_keyword contained mkdir mknod mkstring mod
+syn keyword txl_keyword contained multi multi-sort n-choose-k n-perm-k
+syn keyword txl_keyword contained nilf none not nreverse
 syn keyword txl_keyword contained null nullify num-chr num-str
 syn keyword txl_keyword contained numberp oddp op open-command
 syn keyword txl_keyword contained open-directory open-file open-files open-files*
@@ -126,57 +128,59 @@ syn keyword txl_keyword contained prop proper-listp push pushhash
 syn keyword txl_keyword contained put-byte put-char put-line put-string
 syn keyword txl_keyword contained pwd qquote quasi quasilist
 syn keyword txl_keyword contained quote rand random random-fixnum
-syn keyword txl_keyword contained random-state-p range range* rcomb
-syn keyword txl_keyword contained read readlink real-time-stream-p reduce-left
-syn keyword txl_keyword contained reduce-right ref refset regex-compile
-syn keyword txl_keyword contained regex-parse regexp regsub rehome-sym
-syn keyword txl_keyword contained remhash remove-if remove-if* remove-path
-syn keyword txl_keyword contained remq remq* remql remql*
-syn keyword txl_keyword contained remqual remqual* rename-path repeat
-syn keyword txl_keyword contained replace replace-list replace-str replace-vec
-syn keyword txl_keyword contained rest return return-from reverse
-syn keyword txl_keyword contained rlcp rperm rplaca rplacd
-syn keyword txl_keyword contained run s-ifblk s-ifchr s-ifdir
-syn keyword txl_keyword contained s-ififo s-iflnk s-ifmt s-ifreg
-syn keyword txl_keyword contained s-ifsock s-irgrp s-iroth s-irusr
-syn keyword txl_keyword contained s-irwxg s-irwxo s-irwxu s-isgid
-syn keyword txl_keyword contained s-isuid s-isvtx s-iwgrp s-iwoth
-syn keyword txl_keyword contained s-iwusr s-ixgrp s-ixoth s-ixusr
-syn keyword txl_keyword contained search search-regex search-str search-str-tree
-syn keyword txl_keyword contained second seek-stream select seqp
-syn keyword txl_keyword contained set set-diff set-hash-userdata set-sig-handler
-syn keyword txl_keyword contained sethash setlogmask sh sig-abrt
-syn keyword txl_keyword contained sig-alrm sig-bus sig-check sig-chld
-syn keyword txl_keyword contained sig-cont sig-fpe sig-hup sig-ill
-syn keyword txl_keyword contained sig-int sig-io sig-iot sig-kill
-syn keyword txl_keyword contained sig-lost sig-pipe sig-poll sig-prof
-syn keyword txl_keyword contained sig-pwr sig-quit sig-segv sig-stkflt
-syn keyword txl_keyword contained sig-stop sig-sys sig-term sig-trap
-syn keyword txl_keyword contained sig-tstp sig-ttin sig-ttou sig-urg
-syn keyword txl_keyword contained sig-usr1 sig-usr2 sig-vtalrm sig-winch
-syn keyword txl_keyword contained sig-xcpu sig-xfsz sin sixth
-syn keyword txl_keyword contained size-vec some sort source-loc
-syn keyword txl_keyword contained source-loc-str span-str splice split-str
-syn keyword txl_keyword contained split-str-set sqrt stat stdlib
-syn keyword txl_keyword contained str< str<= str= str>
-syn keyword txl_keyword contained str>= stream-get-prop stream-set-prop streamp
-syn keyword txl_keyword contained string-extend string-lt stringp sub
-syn keyword txl_keyword contained sub-list sub-str sub-vec symacrolet
-syn keyword txl_keyword contained symbol-function symbol-name symbol-package symbol-value
-syn keyword txl_keyword contained symbolp symlink sys-qquote sys-splice
-syn keyword txl_keyword contained sys-unquote syslog tan third
+syn keyword txl_keyword contained random-state-p range range* range-regex
+syn keyword txl_keyword contained rcomb read readlink real-time-stream-p
+syn keyword txl_keyword contained reduce-left reduce-right ref refset
+syn keyword txl_keyword contained regex-compile regex-parse regexp regsub
+syn keyword txl_keyword contained rehome-sym remhash remove-if remove-if*
+syn keyword txl_keyword contained remove-path remq remq* remql
+syn keyword txl_keyword contained remql* remqual remqual* rename-path
+syn keyword txl_keyword contained repeat replace replace-list replace-str
+syn keyword txl_keyword contained replace-vec rest ret retf
+syn keyword txl_keyword contained return return-from reverse rlcp
+syn keyword txl_keyword contained rperm rplaca rplacd run
+syn keyword txl_keyword contained s-ifblk s-ifchr s-ifdir s-ififo
+syn keyword txl_keyword contained s-iflnk s-ifmt s-ifreg s-ifsock
+syn keyword txl_keyword contained s-irgrp s-iroth s-irusr s-irwxg
+syn keyword txl_keyword contained s-irwxo s-irwxu s-isgid s-isuid
+syn keyword txl_keyword contained s-isvtx s-iwgrp s-iwoth s-iwusr
+syn keyword txl_keyword contained s-ixgrp s-ixoth s-ixusr search
+syn keyword txl_keyword contained search-regex search-str search-str-tree second
+syn keyword txl_keyword contained seek-stream select seqp set
+syn keyword txl_keyword contained set-diff set-hash-userdata set-sig-handler sethash
+syn keyword txl_keyword contained setlogmask sh sig-abrt sig-alrm
+syn keyword txl_keyword contained sig-bus sig-check sig-chld sig-cont
+syn keyword txl_keyword contained sig-fpe sig-hup sig-ill sig-int
+syn keyword txl_keyword contained sig-io sig-iot sig-kill sig-lost
+syn keyword txl_keyword contained sig-pipe sig-poll sig-prof sig-pwr
+syn keyword txl_keyword contained sig-quit sig-segv sig-stkflt sig-stop
+syn keyword txl_keyword contained sig-sys sig-term sig-trap sig-tstp
+syn keyword txl_keyword contained sig-ttin sig-ttou sig-urg sig-usr1
+syn keyword txl_keyword contained sig-usr2 sig-vtalrm sig-winch sig-xcpu
+syn keyword txl_keyword contained sig-xfsz sin sixth size-vec
+syn keyword txl_keyword contained some sort source-loc source-loc-str
+syn keyword txl_keyword contained span-str splice split-str split-str-set
+syn keyword txl_keyword contained sqrt stat stdlib str<
+syn keyword txl_keyword contained str<= str= str> str>=
+syn keyword txl_keyword contained stream-get-prop stream-set-prop streamp string-extend
+syn keyword txl_keyword contained string-lt stringp sub sub-list
+syn keyword txl_keyword contained sub-str sub-vec symacrolet symbol-function
+syn keyword txl_keyword contained symbol-name symbol-package symbol-value symbolp
+syn keyword txl_keyword contained symlink sys-qquote sys-splice sys-unquote
+syn keyword txl_keyword contained syslog tan tf third
 syn keyword txl_keyword contained throw throwf time time-fields-local
 syn keyword txl_keyword contained time-fields-utc time-string-local time-string-utc time-usec
-syn keyword txl_keyword contained tofloat toint tok-str tostring
-syn keyword txl_keyword contained tostringp tree-bind tree-case tree-find
-syn keyword txl_keyword contained trie-add trie-compress trim-str true
-syn keyword txl_keyword contained trunc tuples typeof unget-byte
-syn keyword txl_keyword contained unget-char unless unquote until
-syn keyword txl_keyword contained upcase-str update url-decode url-encode
-syn keyword txl_keyword contained usleep uw-protect vec vec-push
-syn keyword txl_keyword contained vec-set-length vecref vector vector-list
-syn keyword txl_keyword contained vectorp when where while
-syn keyword txl_keyword contained with-saved-vars zerop
+syn keyword txl_keyword contained tofloat toint tok-str tok-where
+syn keyword txl_keyword contained tostring tostringp transpose tree-bind
+syn keyword txl_keyword contained tree-case tree-find trie-add trie-compress
+syn keyword txl_keyword contained trim-str true trunc tuples
+syn keyword txl_keyword contained typeof unget-byte unget-char unless
+syn keyword txl_keyword contained unquote until upcase-str update
+syn keyword txl_keyword contained url-decode url-encode usleep uw-protect
+syn keyword txl_keyword contained vec vec-push vec-set-length vecref
+syn keyword txl_keyword contained vector vector-list vectorp when
+syn keyword txl_keyword contained where while with-saved-vars zerop
+syn keyword txl_keyword contained zip
 
 syn match txr_error "@[\t ]*[*]\?[\t ]*."
 syn match txr_nested_error "[^\t `]\+" contained