1 files changed, 167 insertions, 0 deletions
diff --git a/src/cmd/gotry/gotry b/src/cmd/gotry/gotry
new file mode 100755
index 000000000..52c5d2d58
--- /dev/null
+++ b/src/cmd/gotry/gotry
@@ -0,0 +1,167 @@
+#!/usr/bin/env bash
+# Copyright 2010 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# Using all the non-test *.go files in the named directory, write
+# out a file /tmp/$USER.try.go to evaluate the expressions on the
+# command line, perhaps to discover a function or method that
+# gives the desired results.  See usage message.
+# Compile the program and run it.
+
+# Makes egrep,grep work better in general if we put them
+# in ordinary C mode instead of what the current language is.
+unset LANG
+export LC_ALL=C
+export LC_CTYPE=C
+
+export GOROOT=${GOROOT:-"@@GOROOT@@"}
+eval $(gomake -j1 --no-print-directory -f "$GOROOT"/src/Make.inc go-env)
+if [ -z "$O" ]; then
+	echo 'missing $O - maybe no Make.$GOARCH?' 1>&2
+	exit 2
+fi
+
+# Allow overrides
+GC="${_GC:-$GC} -I _test"
+GL="${GL:-$LD} -L _test"
+AS="$AS"
+CC="$CC"
+LD="$LD"
+export GC GL O AS CC LD
+
+# Macros for tab and quotes for easier readability.
+T='	'
+BQ='`'
+SQ="'"
+DQ='"'
+SD="$SQ$DQ"
+DS="$DQ$SQ"
+
+usage="usage: gotry [packagedirectory] expression ...
+Given one expression, gotry attempts to evaluate that expression.
+Given multiple expressions, gotry treats them as a list of arguments
+and result values and attempts to find a function in the package
+that, given the first few expressions as arguments, evaluates to
+the remaining expressions as results.  If the first expression has
+methods, it will also search for applicable methods.
+
+If there are multiple expressions, a package directory must be
+specified. If there is a package argument, the expressions are
+evaluated in an environment that includes
+	import . ${DQ}packagedirectory${DQ}
+
+Examples:
+	gotry 3+4
+		# evaluates to 7
+	gotry strings ${SD}abc${DS} ${SD}c${DS} 7-5
+		# finds strings.Index etc.
+	gotry regexp ${SQ}MustCompile(${DQ}^[0-9]+${DQ})${SQ} ${SD}12345${DS} true
+		# finds Regexp.MatchString
+
+"
+
+function fail() {
+	echo 2>&1 "$@"
+	exit 2
+}
+
+case $# in
+	0)
+		fail "$usage"
+		;;
+	*)
+		case "$1" in
+		-*help|-*'?'|'?')
+			fail "$usage"
+		esac
+		if test -d "$GOROOT/src/pkg/$1"
+		then
+			pkg=$(basename $1)
+			dir=$GOROOT/src/pkg/$1
+			importdir=$1
+			shift
+			case "$pkg" in
+			os|syscall)
+				fail "gotry: cannot try packages os or syscall; they are too dangerous"
+			esac
+		fi
+		;;
+esac
+
+spaces='[ 	][ 	]*'
+
+function getFunctions() {
+	if [ "$pkg" = "" ]
+	then
+		return
+	fi
+	for file in $dir/*.go
+	do
+		case $file in
+		*_test*)
+			continue
+		esac
+		grep "func$spaces[A-Z]" $file | # TODO: should be Unicode upper case
+			sed "s/func$spaces//;s/(.*//"
+	done | sort -u
+}
+
+# Generate list of public functions.
+functions=$(getFunctions)
+
+# Write file to compile
+rm -f /tmp/$USER.try.go
+(
+cat <<'!'
+package main
+
+import (
+	"os"
+	"try"
+!
+
+if [ "$pkg" != "" ]
+then
+	echo "$T" . '"'$importdir'"'
+fi
+
+cat <<!
+)
+func main() {
+	try.Main("$pkg", firstArg, functions, args)
+}
+var functions = map[string] interface{}{
+!
+
+for i in $functions
+do
+	echo "$T"'"'$i'": '$i','
+done
+echo "}"
+
+echo 'var args = []interface{}{'
+
+if [ $# = 1 ]
+then
+	echo "${T}toSlice($1)",
+else
+for i
+	do
+		echo "$T$i",
+	done
+fi
+echo "}"
+
+cat <<!
+var firstArg = $BQ$1$BQ
+var _ os.Error
+func toSlice(a ...interface{}) []interface{} { return a }
+!
+
+)>/tmp/$USER.try.go
+
+$GC -o /tmp/$USER.try.$O /tmp/$USER.try.go &&
+$GL -o /tmp/$USER.try /tmp/$USER.try.$O &&
+/tmp/$USER.try "_$@"
+rm -f /tmp/$USER.try /tmp/$USER.try.go /tmp/$USER.try.$O