From a23a0aa8740a7781f716b181e4a92a94ab9303d2 Mon Sep 17 00:00:00 2001
From: Jeff Bezanson <bezanson@post.harvard.edu>
Date: Sat, 14 May 2011 01:29:35 -0400
Subject: [PATCH] parsing 2.*3 as 2 .* 3 closes #18

---
 src/flisp/iostream.c | 14 ++++++++++++++
 src/julia-parser.scm | 21 ++++++++++++++-------
 test/tests.j         |  1 +
 3 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/src/flisp/iostream.c b/src/flisp/iostream.c
index 2419f8c7985ae..489672d605cef 100644
--- a/src/flisp/iostream.c
+++ b/src/flisp/iostream.c
@@ -160,6 +160,19 @@ value_t fl_ioputc(value_t *args, u_int32_t nargs)
     return fixnum(ios_pututf8(s, wc));
 }
 
+value_t fl_ioungetc(value_t *args, u_int32_t nargs)
+{
+    argcount("io.ungetc", nargs, 2);
+    ios_t *s = toiostream(args[0], "io.ungetc");
+    if (!iscprim(args[1]) || ((cprim_t*)ptr(args[1]))->type != wchartype)
+        type_error("io.ungetc", "wchar", args[1]);
+    uint32_t wc = *(uint32_t*)cp_data((cprim_t*)ptr(args[1]));
+    if (wc >= 0x80) {
+        lerror(ArgError, "io_ungetc: unicode not yet supported");
+    }
+    return fixnum(ios_ungetc((int)wc,s));
+}
+
 value_t fl_ioflush(value_t *args, u_int32_t nargs)
 {
     argcount("io.flush", nargs, 1);
@@ -419,6 +432,7 @@ static builtinspec_t iostreamfunc_info[] = {
     { "io.seek" , fl_ioseek },
     { "io.pos",   fl_iopos },
     { "io.getc" , fl_iogetc },
+    { "io.ungetc", fl_ioungetc },
     { "io.putc" , fl_ioputc },
     { "io.peekc" , fl_iopeekc },
     { "io.discardbuffer", fl_iopurge },
diff --git a/src/julia-parser.scm b/src/julia-parser.scm
index 73ec08f822a77..b0ba0f52d3f5e 100644
--- a/src/julia-parser.scm
+++ b/src/julia-parser.scm
@@ -99,7 +99,10 @@
 				      (char<=? c #\9))
 				 (char>=? c #\uA1)
 				 (eqv? c #\_)))
+;; characters that can be in an operator
 (define (opchar? c) (string.find op-chars c))
+;; characters that can follow . in an operator
+(define (dot-opchar? c) (and (char? c) (string.find "*^/\\" c)))
 (define (operator? c) (memq c operators))
 
 (define (skip-to-eol port)
@@ -159,9 +162,13 @@
 					(and (>= c #\A) (<= c #\F)))))))
 	    (allow #\.)))
     (read-digs)
-    (allow #\.)
-    (read-digs)
-    (disallow #\.)
+    (if (eqv? (peek-char port) #\.)
+	(begin (read-char port)
+	       (if (dot-opchar? (peek-char port))
+		   (io.ungetc port #\.)
+		   (begin (write-char #\. str)
+			  (read-digs)
+			  (disallow #\.)))))
     (if (or (allow #\e) (allow #\E))
 	(begin (or (allow #\+) (allow #\-))
 	       (read-digs)
@@ -183,12 +190,10 @@
   (let ((c (peek-char port)))
     (cond ((or (eof-object? c) (newline? c))  (read-char port))
 
-	  ((char-numeric? c)    (read-number port))
-	  
-	  ((identifier-char? c) (accum-julia-symbol c port))
-
 	  ((special-char? c)    (read-char port))
 
+	  ((char-numeric? c)    (read-number port))
+	  
 	  ((eqv? c #\#)         (skip-to-eol port) (next-token port s))
 	  
 	  ; . is difficult to handle; it could start a number or operator
@@ -206,6 +211,8 @@
 	  
 	  ((opchar? c)  (read-operator port c))
 
+	  ((identifier-char? c) (accum-julia-symbol c port))
+
 	  #;((eqv? c #\")
 	   (with-exception-catcher
 	    (lambda (e)
diff --git a/test/tests.j b/test/tests.j
index 51c139659c6ab..18c8a968e758c 100644
--- a/test/tests.j
+++ b/test/tests.j
@@ -76,6 +76,7 @@ nttest1{n}(x::NTuple{n,Int32}) = n
 @assert 2+3 == 5
 @assert 2.+3. == 5.
 @assert 2*3 == 6
+@assert 2.*3 == 6
 @assert 2. * 3. == 6.
 @assert min(1.0,1) == 1