- Added expand-template and expand-template.scm

2 files changed, 66 insertions, 0 deletions

diff --git a/bin/expand-template b/bin/expand-template
new file mode 100755
index 0000000000..177f73fd61
--- /dev/null
+++ b/bin/expand-template
@@ -0,0 +1,16 @@
+#!/bin/sh
+
+# $Id$
+
+SOURCE="$0";
+while [ -h "$SOURCE" ]; do
+    LOOKUP="`ls -ld "$SOURCE"`";
+    TARGET="`expr "$LOOKUP" : '.*-> \(.*\)$'`";
+    if expr "${TARGET:-.}/" : '/.*/$' > /dev/null; then
+        SOURCE="${TARGET:-.}";
+    else
+        SOURCE="`dirname "$SOURCE"`/${TARGET:-.}";
+    fi;
+done;
+
+scsh -e main -s "$SOURCE.scm" "$@"
diff --git a/bin/expand-template.scm b/bin/expand-template.scm
new file mode 100755
index 0000000000..96147abf85
--- /dev/null
+++ b/bin/expand-template.scm
@@ -0,0 +1,50 @@
+#!/home/linuxsoft/bin/scsh \
+-e main -s
+!#
+
+;; $Id$
+
+(define expand
+  (let ((variable-rx (rx "[#" (submatch (+ (| alphanum ("-")))) "#]")))
+    (lambda (env in-port out-port)
+      (awk (read-line in-port 'concat) (line) ()
+           (#t (regexp-substitute/global out-port
+                                         variable-rx
+                                         line
+                                         'pre
+                                         (lambda (match)
+                                           (let* ((var (string->symbol
+                                                        (match:substring match 1)))
+                                                  (expansion (assoc var env)))
+                                             (if expansion
+                                                 (cdr expansion)
+                                                 (error "Unknown variable in template"
+                                                        var))))
+                                         'post))))))
+
+(define (display-usage-and-exit prog)
+  (format #t "Usage: ~a <rule-file> <template-file> <target-file>~%" prog)
+  (format #t "where <rule-file> is a Scheme file containing expansion rules,~%")
+  (format #t "      <template-file> is the template file, and~%")
+  (format #t "      <target-file> is the file to generate.~%")
+  (exit 1))
+
+(define initial-environment
+  '((do-not-edit . "DO NOT EDIT. Automatically generated file!")))
+
+(define (main cmd-line)
+  (let ((prog (car cmd-line))
+        (args (cdr cmd-line)))
+    (if (= (length args) 3)
+        (let ((rule (first args))
+              (tmpl (second args))
+              (file (third args)))
+          (load rule)
+          (call-with-input-file tmpl
+            (lambda (in-port)
+              (call-with-output-file file
+                (lambda (out-port)
+                  (expand (append initial-environment (make-env file))
+                          in-port
+                          out-port))))))
+        (display-usage-and-exit prog))))