From 39fba10b45e247bf94cdca222334c7cd4eb40087 Mon Sep 17 00:00:00 2001 From: dgp Date: Mon, 10 Jun 2019 18:44:18 +0000 Subject: More localized documentation of lazy operators. --- doc/expr.n | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/doc/expr.n b/doc/expr.n index 2a0af7e..58a4b7f 100644 --- a/doc/expr.n +++ b/doc/expr.n @@ -106,7 +106,7 @@ Then the command on the left side of each of the lines below will produce the value on the right side of the line: .PP .CS -.ta 6c +.ta 8c \fBexpr\fR 3.1 + $a \fI6.1\fR \fBexpr\fR 2 + "$a.$b" \fI5.6\fR \fBexpr\fR 4*[llength "6 2"] \fI8\fR @@ -201,18 +201,23 @@ Bit-wise OR. Valid for integer operands only. Logical AND. Produces a 1 result if both operands are non-zero, 0 otherwise. Valid for boolean and numeric (integers or floating-point) operands only. +This operator evaluates lazily; it only evaluates its second operand if it +must in order to determine its result. .TP 20 \fB||\fR . Logical OR. Produces a 0 result if both operands are zero, 1 otherwise. Valid for boolean and numeric (integers or floating-point) operands only. +This operator evaluates lazily; it only evaluates its second operand if it +must in order to determine its result. .TP 20 -\fIx\fB?\fIy\fB:\fIz\fR +\fIx \fB?\fI y \fB:\fI z\fR . If-then-else, as in C. If \fIx\fR evaluates to non-zero, then the result is the value of \fIy\fR. Otherwise the result is the value of \fIz\fR. The \fIx\fR operand must have a boolean or numeric value. +This operator evaluates lazily; it evaluates only one of \fIy\fR or \fIz\fR. .PP See the C manual for more details on the results produced by each operator. -- cgit v0.12