SYNOPSIS<pop $&var [$index]>
DESCRIPTION
The pop
function "pops" (removes) a value from $&var
,
at the index given by $index
(default 0). The target variable
must be specified with pass-by-reference syntax - i.e. $&var
not $var
- because it will be modified. Passing it by value
would not let it be modified, which might otherwise be a silent bug -
hence an error is generated if it is passed by value.
The effective $index
value may be zero through one less than
the number of pre-existing values of $var
. Explicit negative
$index
values are interpreted as offsets from the end of
$var
, e.g. -1 is the last value. Out of range or
non-integral $index
values are a run-time error. An
empty-string or zero-values $index
is taken as the default,
which is 0.
DIAGNOSTICS
The pop
function returns the popped-off value in $ret
.
EXAMPLE<a name=main>
<$var = "a" "b" "c">
<pop $&var 1>
After: <loop $var> $var </loop>
ret is $ret
</a>
The output of the above example would be:
After: a c
ret is b
CAVEATS
The pop
function is only valid in syntaxversion
8.
SEE ALSOpush