[Guile-commits] 10/36: read nil/t as #nil/#t

[Christopher Allan Webber]

cwebber pushed a commit to branch wip-elisp
in repository guile.

commit e4464967f744fb5537c2f8af971e5494598e3bca
Author: Robin Templeton <address@hidden>
Date:   Thu Jun 19 23:37:36 2014 -0400

    read nil/t as #nil/#t
    
    (Best-ability ChangeLog annotation added by Christopher Allan Webber.)
    
    * module/language/elisp/lexer.scm (lex): Update to handle #nil / #t.
---
 module/language/elisp/lexer.scm |   30 ++++++++++++++++++------------
 1 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/module/language/elisp/lexer.scm b/module/language/elisp/lexer.scm
index 8152a11..826f6df 100644
--- a/module/language/elisp/lexer.scm
+++ b/module/language/elisp/lexer.scm
@@ -370,18 +370,24 @@
            (lambda (type str)
              (case type
                ((symbol)
-                ;; str could be empty if the first character is already
-                ;; something not allowed in a symbol (and not escaped)!
-                ;; Take care about that, it is an error because that
-                ;; character should have been handled elsewhere or is
-                ;; invalid in the input.
-                (if (zero? (string-length str))
-                    (begin
-                      ;; Take it out so the REPL might not get into an
-                      ;; infinite loop with further reading attempts.
-                      (read-char port)
-                      (error "invalid character in input" c))
-                    (return 'symbol (string->symbol str))))
+                (cond
+                 ((equal? str "nil")
+                  (return 'symbol #nil))
+                 ((equal? str "t")
+                  (return 'symbol #t))
+                 (else
+                  ;; str could be empty if the first character is already
+                  ;; something not allowed in a symbol (and not escaped)!
+                  ;; Take care about that, it is an error because that
+                  ;; character should have been handled elsewhere or is
+                  ;; invalid in the input.
+                  (if (zero? (string-length str))
+                      (begin
+                        ;; Take it out so the REPL might not get into an
+                        ;; infinite loop with further reading attempts.
+                        (read-char port)
+                        (error "invalid character in input" c))
+                      (return 'symbol (string->symbol str))))))
                ((integer)
                 ;; In elisp, something like "1." is an integer, while
                 ;; string->number returns an inexact real.  Thus we need