New <case.h> header and macro.

This provides a portable case statement implemented directly
as switch on GNU Awk, and using other approaches on other Awks
that do not have switch.

1 files changed, 54 insertions, 0 deletions

diff --git a/testcases-case b/testcases-case
new file mode 100644
index 0000000..6e62412
--- /dev/null
+++ b/testcases-case
@@ -0,0 +1,54 @@
+1:
+$cppawk '
+#include <case.h>
+BEGIN {
+#if defined case_temps && defined case && defined of && \
+    defined matching && defined cbreak && defined otherwise
+  print 1
+#endif
+}'
+:
+1
+--
+2:
+printf "%s\n" foo bar xyzzy x b | $cppawk '
+#include <case.h>
+{
+   case ($0) {
+     of ("foo")
+       print "** foo case: fallthrough!"
+       cfall;
+     of ("bar", "xyzzy") {
+       print "** bar/xyzzy case"
+       cbreak;
+     }
+     matching (/x/)
+       print "** /x/ case"
+       cbreak;
+     otherwise
+       print "** default"
+       cbreak;
+   }
+}'
+:
+** foo case: fallthrough!
+** bar/xyzzy case
+** bar/xyzzy case
+** bar/xyzzy case
+** /x/ case
+** default
+--
+3:
+$cppawk '
+#include <case.h>
+function f(arg, case_temps)
+{
+  case (arg) {
+    of (1, 2, 3) cret(arg * 10)
+    otherwise    cret(-arg)
+  }
+}
+
+BEGIN { print f(1), f(2), f(3), f(4) }'
+:
+10 20 30 -4