X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Fmacros.lisp;h=701631231c0e2217bb29f0e39f3eada7f8d63117;hb=dc71db379ab4162a45c393a2e828f619dae9fa32;hp=3e1e337f764e6e6528956989964d829ad086c39b;hpb=3c5609fe910bae51ff885c8cfd4be879151e7489;p=sbcl.git

diff --git a/src/compiler/macros.lisp b/src/compiler/macros.lisp
index 3e1e337..7016312 100644
--- a/src/compiler/macros.lisp
+++ b/src/compiler/macros.lisp
@@ -944,3 +944,29 @@
 (defmacro position-or-lose (&rest args)
   `(or (position ,@args)
        (error "shouldn't happen?")))
+
+;;; user-definable compiler io syntax
+
+;;; We use WITH-SANE-IO-SYNTAX to provide safe defaults, and provide
+;;; *COMPILER-PRINT-VARIABLE-ALIST* for user customization.
+(defvar *compiler-print-variable-alist* nil
+  #!+sb-doc
+  "an association list describing new bindings for special variables
+to be used by the compiler for error-reporting, etc. Eg.
+
+ ((*PRINT-LENGTH* . 10) (*PRINT-LEVEL* . 6) (*PRINT-PRETTY* . NIL))
+
+The variables in the CAR positions are bound to the values in the CDR
+during the execution of some debug commands. When evaluating arbitrary
+expressions in the debugger, the normal values of the printer control
+variables are in effect.
+
+Initially empty, *COMPILER-PRINT-VARIABLE-ALIST* is Typically used to
+specify bindings for printer control variables.")
+
+(defmacro with-compiler-io-syntax (&body forms)
+  `(with-sane-io-syntax
+    (progv
+        (nreverse (mapcar #'car *compiler-print-variable-alist*))
+        (nreverse (mapcar #'cdr *compiler-print-variable-alist*))
+      ,@forms)))