merge trunkdkf_notifier_poll

1 files changed, 17 insertions, 4 deletions

diff --git a/doc/expr.n b/doc/expr.n
index 2ecd501..6d965fb 100644
--- a/doc/expr.n
+++ b/doc/expr.n
@@ -134,7 +134,20 @@ Multiply, divide, remainder.  None of these operators may be
 applied to string operands, and remainder may be applied only
 to integers.
 The remainder will always have the same sign as the divisor and
-an absolute value smaller than the divisor.
+an absolute value smaller than the absolute value of the divisor.
+.RS
+.PP
+When applied to integers, the division and remainder operators can be
+considered to partition the number line into a sequence of equal-sized
+adjacent non-overlapping pieces where each piece is the size of the divisor;
+the division result identifies which piece the divisor lay within, and the
+remainder result identifies where within that piece the divisor lay. A
+consequence of this is that the result of
+.QW "-57 \fB/\fR 10"
+is always -6, and the result of
+.QW "-57 \fB%\fR 10"
+is always 3.
+.RE
 .TP 20
 \fB+\0\0\-\fR
 .
@@ -326,6 +339,7 @@ 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
@@ -337,12 +351,11 @@ is that produced by the \fB%g\fR format specifier of Tcl's
 .PP
 .CS
 \fBexpr\fR {"0x03" > "2"}
-\fBexpr\fR {"0y" < "0x12"}
+\fBexpr\fR {"0y" > "0x12"}
 .CE
 .PP
 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