| Commit | Line | Data |
|---|
| c07a80fd |
1 | package vars; |
| 2 | |
| 3b825e41 |
3 | use 5.006; |
| fb73857a |
4 | |
| e6d61def |
5 | our $VERSION = '1.01'; |
| 3d842d7f |
6 | |
| 7 | use warnings::register; |
| e6d61def |
8 | use strict qw(vars subs); |
| fb73857a |
9 | |
| 10 | sub import { |
| 11 | my $callpack = caller; |
| 386f5e9f |
12 | my ($pack, @imports) = @_; |
| 13 | my ($sym, $ch); |
| 7eb43e02 |
14 | foreach (@imports) { |
| 15 | ($ch, $sym) = unpack('a1a*', $_); |
| 014aafb8 |
16 | if ($sym =~ tr/A-Za-z_0-9//c) { |
| 15313f9c |
17 | # time for a more-detailed check-up |
| 7eb43e02 |
18 | if ($sym =~ /^\w+[[{].*[]}]$/) { |
| 15313f9c |
19 | require Carp; |
| 20 | Carp::croak("Can't declare individual elements of hash or array"); |
| d3a7d8c7 |
21 | } elsif (warnings::enabled() and length($sym) == 1 and $sym !~ tr/a-zA-Z//) { |
| 22 | warnings::warn("No need to declare built-in vars"); |
| 13368207 |
23 | } elsif (($^H &= strict::bits('vars')) && |
| 8a305e7f |
24 | # Either no 'use utf8' or if utf8, no non-word |
| 13368207 |
25 | ($^H & 0x00800000 == 0 || # matches $utf8::hint_bits |
| 8a305e7f |
26 | $sym =~ /\W/) ) { |
| 13368207 |
27 | require Carp; |
| 28 | Carp::croak("'$_' is not a valid variable name under strict vars"); |
| 15313f9c |
29 | } |
| 30 | } |
| 7eb43e02 |
31 | $sym = "${callpack}::$sym" unless $sym =~ /::/; |
| 32 | *$sym = |
| 33 | ( $ch eq "\$" ? \$$sym |
| 34 | : $ch eq "\@" ? \@$sym |
| 35 | : $ch eq "\%" ? \%$sym |
| 36 | : $ch eq "\*" ? \*$sym |
| 37 | : $ch eq "\&" ? \&$sym |
| fb73857a |
38 | : do { |
| 39 | require Carp; |
| 7eb43e02 |
40 | Carp::croak("'$_' is not a valid variable name"); |
| fb73857a |
41 | }); |
| 42 | } |
| 43 | }; |
| 44 | |
| 45 | 1; |
| 46 | __END__ |
| 47 | |
| c07a80fd |
48 | =head1 NAME |
| 49 | |
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50 | vars - Perl pragma to predeclare global variable names (obsolete) |
| c07a80fd |
51 | |
| 52 | =head1 SYNOPSIS |
| 53 | |
| 54 | use vars qw($frob @mung %seen); |
| 55 | |
| 56 | =head1 DESCRIPTION |
| 57 | |
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58 | NOTE: For variables in the current package, the functionality provided |
| 59 | by this pragma has been superseded by C<our> declarations, available |
| 60 | in Perl v5.6.0 or later. See L<perlfunc/our>. |
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61 | |
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62 | This will predeclare all the variables whose names are |
| 63 | in the list, allowing you to use them under "use strict", and |
| 64 | disabling any typo warnings. |
| 65 | |
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66 | Unlike pragmas that affect the C<$^H> hints variable, the C<use vars> and |
| 67 | C<use subs> declarations are not BLOCK-scoped. They are thus effective |
| 68 | for the entire file in which they appear. You may not rescind such |
| 69 | declarations with C<no vars> or C<no subs>. |
| 70 | |
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71 | Packages such as the B<AutoLoader> and B<SelfLoader> that delay |
| 72 | loading of subroutines within packages can create problems with |
| 73 | package lexicals defined using C<my()>. While the B<vars> pragma |
| 74 | cannot duplicate the effect of package lexicals (total transparency |
| 75 | outside of the package), it can act as an acceptable substitute by |
| 76 | pre-declaring global symbols, ensuring their availability to the |
| 77 | later-loaded routines. |
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78 | |
| ee580363 |
79 | See L<perlmodlib/Pragmatic Modules>. |
| c07a80fd |
80 | |
| 81 | =cut |
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