Return::Deep - deeply returns through multiple layers at once, and special wantarray functions
use Return::Deep;
sub a {
b();
# never goes here
}
sub b {
my $wantarray = deep_wantarray(2);
# got a true value, because of `@ret = a();`
deep_ret(2, 'Hi', 42);
}
my @ret = a();
# got ('Hi', 42) here
my @outer_ret = ret_bound {
my @regex_ret = ret_bound {
my @inner_ret = ret_bound {
my $wantarray = sym_wantarray('inner');
# got a true value, because of
# `@inner_ret = ret_bound {...} 'inner';`
if( .2 < rand ) {
sym_ret('inner', 43); # @inner_ret got 43
}
elsif( .5 < rand ) {
sym_ret('Error::SomeError', 45); # @regex_ret got 45
}
else {
sym_ret('any', 43); # @outer_ret got 44
}
} 'inner'; # catch 'inner'
} qr/^Error::/; # catch all symbols which begin with 'Error::' by regex
}; # catch all symbols without a catch symbol
Deeply returns through multiple layers at once.
-
deep_ret($depth, @return_value)
If
$depth
= 1, it performs like a normal return.If
$depth
<= 0, it performs like a normal list.If
$depth
> 1, it returns through many layers, including subs and eval blocks. -
sym_ret($symbol, @return_value)
Return through many layers, until the
$symbol
is catched by a matchedret_bound
. -
ret_bound {CODE_BLOCK} $catch_symbol
-
ret_bound {CODE_BLOCK}
Catch matched
sym_ret
s. Without the$catch_symbol
, it will catch all thesym_ret
.$catch_symbol
could be a string or a regular expression (qr/something/
). If$catch_symbol
is a string, it will catchsym_ret
with an exactly match. If$catch_symbol
is a regular expression, it will catchsym_ret
with a regular expression test.(
$catch_symbol
with regular expresion is not supported before Perl 5.10) -
$wantarray = deep_wantarray($depth)
Like builtin function
wantarray
, but at specified$depth
. -
$wantarray = sym_wantarray($symbol)
Like builtin function
wantarray
, but at certainret_bound
which catch the <$symbol>.
Tested on Perl version 5.30.2, 5.28.2, 5.26.3, 5.24.4, 5.22.4, 5.20.3, 5.18.4, 5.16.3, 5.14.4, 5.12.5, 5.10.1, 5.8.9.
This mod's github https://github.com/CindyLinz/Perl-Return-Deep. It's welcome to discuss with me when you encounter bugs, or if you think that some patterns are also useful but the mod didn't provide them yet.
Cindy Wang (CindyLinz), cindy@cpan.org
Copyright (C) 2020 by Cindy Wang (CindyLinz)
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.30.1 or, at your option, any later version of Perl 5 you may have available.