[Bug 3525462]: Document what relational operators really do with string args.

2 files changed, 9 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index 1369602..c841b77 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2012-05-17  Donal K. Fellows  <dkf@users.sf.net>
+
+	* doc/expr.n: [Bug 3525462]: Corrected statement about what happens
+	when comparing "0y" and "0x12"; the previously documented behavior was
+	actually a subtle bug (now long-corrected).
+
 2012-05-13  Jan Nijtmans  <nijtmans@users.sf.net>
 
 	* win/tclWinDde.c:   Protect against receiving strings without ending \0,
diff --git a/doc/expr.n b/doc/expr.n
index 8d6a8ae..177e127 100644
--- a/doc/expr.n
+++ b/doc/expr.n
@@ -298,6 +298,7 @@ returns \fB4.0\fR, not \fB4\fR.
 String values may be used as operands of the comparison operators,
 although the expression evaluator tries to do comparisons as integer
 or floating-point when it can,
+i.e., when all arguments to the operator allow numeric interpretations,
 except in the case of the \fBeq\fR and \fBne\fR operators.
 If one of the operands of a comparison is a string and the other
 has a numeric value, a canonical string representation of the numeric
@@ -308,11 +309,10 @@ is that produced by the \fB%g\fR format specifier of Tcl's
 \fBformat\fR command.  For example, the commands
 .CS
 \fBexpr {"0x03" > "2"}\fR
-\fBexpr {"0y" < "0x12"}\fR
+\fBexpr {"0y" > "0x12"}\fR
 .CE
 both return 1.  The first comparison is done using integer
-comparison, and the second is done using string comparison after
-the second operand is converted to the string \fB18\fR.
+comparison, and the second is done using string comparison.
 Because of Tcl's tendency to treat values as numbers whenever
 possible, it is not generally a good idea to use operators like \fB==\fR
 when you really want string comparison and the values of the