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-rw-r--r--doc/apply.n10
1 files changed, 7 insertions, 3 deletions
diff --git a/doc/apply.n b/doc/apply.n
index 1e69e69..22b068d 100644
--- a/doc/apply.n
+++ b/doc/apply.n
@@ -65,6 +65,7 @@ proc apply {fun args} {
This shows how to make a simple general command that applies a transformation
to each element of a list.
.CS
+.ta 2i
proc map {lambda list} {
set result {}
foreach $item $list {
@@ -73,21 +74,24 @@ proc map {lambda list} {
return $result
}
map {x {return [string length $x]:$x}} {a bb ccc dddd}
- \fI=> 1:a 2:bb 3:ccc 4:dddd\fR
+ \fB\(->\fI 1:a 2:bb 3:ccc 4:dddd\fR
map {x {expr {$x**2 + 3*$x - 2}}} {-4 -3 -2 -1 0 1 2 3 4}
- \fI=> 2 -2 -4 -4 -2 2 8 16 26\fR
+ \fB\(->\fI 2 -2 -4 -4 -2 2 8 16 26\fR
.CE
.PP
The \fBapply\fR command is also useful for defining callbacks for use in the
\fBtrace\fR command:
.CS
+.ta 2i
set vbl "123abc"
trace add variable vbl write {\fBapply\fR {v1 v2 op} {
upvar 1 $v1 v
- puts "updated variable to \\"$v\\""
+ puts "updated variable to \e"$v\e""
}}
set vbl 123
+ \fB\(->\fI updated variable to "123"\fR
set vbl abc
+ \fB\(->\fI updated variable to "abc"\fR
.CE
.SH "SEE ALSO"
proc(n), uplevel(n)