Re^3: subroutine bewilderment: how to mimic builtins

I know, but it's as close as possible. Considering the case that is different is an illegal case, I didn't bother confusing the issue by mentioning it.

my $_; doesn't compile for me with Perl v5.8.6. Did you mean tie $_? There's some kind of problem with local $_ when $_ is tied, but 1) that's not likely, and 2) it can be avoided by localizing *_ instead of $_ (as I did in one of my examples).

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Re^4: subroutine bewilderment: how to mimic builtins by ysth (Canon) on Feb 08, 2006 at 04:39 UTC
`my $_;` is intended as a replacement for the not-ideal `local $_;` or `local *_;`. perl591delta: =head2 Lexical `$_` The default variable `$_` can now be lexicalized, by declaring it like any other lexical variable, with a simple `my $_;` [download] The operations that default on `$_` will use the lexically-scoped version of `$_` when it exists, instead of the global `$_`. In a `map` or a `grep` block, if `$_` was previously my'ed, then the `$_` inside the block is lexical as well (and scoped to the block). In a scope where `$_` has been lexicalized, you can still have access to the global version of `$_` by using `$::_`, or, more simply, by overriding the lexical declaration with `our $_`.	[reply] [d/l] [select]

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Re^4: subroutine bewilderment: how to mimic builtins
by ysth (Canon) on Feb 08, 2006 at 04:39 UTC

my $_;

local $_;

local *_;

perl591delta:

=head2 Lexical $_
The default variable $_ can now be lexicalized, by declaring it like any other lexical variable, with a simple
    my $_;
[download]
The operations that default on $_ will use the lexically-scoped version of $_ when it exists, instead of the global $_.
In a map or a grep block, if $_ was previously my'ed, then the $_ inside the block is lexical as well (and scoped to the block).
In a scope where $_ has been lexicalized, you can still have access to the global version of $_ by using $::_, or, more simply, by overriding the lexical declaration with our $_.

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