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=head1 NAME |
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Convert::Scalar - convert between different representations of perl scalars |
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|
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=head1 SYNOPSIS |
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|
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use Convert::Scalar; |
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|
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=head1 DESCRIPTION |
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|
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This module exports various internal perl methods that change the internal |
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representation or state of a perl scalar. All of these work in-place, that |
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is, they modify their scalar argument. No functions are exported by default. |
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|
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The following export tags exist: |
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|
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:utf8 all functions with utf8 in their names |
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:taint all functions with taint in their names |
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|
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=over 4 |
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|
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=cut |
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|
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package Convert::Scalar; |
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|
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BEGIN { |
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$VERSION = 0.06; |
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@ISA = qw(Exporter); |
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@EXPORT_OK = qw(weaken unmagic grow); |
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%EXPORT_TAGS = ( |
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taint => [qw(taint untaint tainted)], |
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utf8 => [qw(utf8 utf8_on utf8_off utf8_valid utf8_upgrade utf8_downgrade utf8_encode utf8_decode utf8_length)], |
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); |
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|
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require Exporter; |
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Exporter::export_ok_tags(keys %EXPORT_TAGS); |
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|
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require XSLoader; |
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XSLoader::load Convert::Scalar, $VERSION; |
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} |
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=item utf8 scalar[, mode] |
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|
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Returns true when the given scalar is marked as utf8, false otherwise. If |
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the optional mode argument is given, also forces the interpretation of the |
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string to utf8 (mode true) or plain bytes (mode false). The actual (byte-) |
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content is not changed. The return value always reflects the state before |
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any modification is done. |
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|
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This function is useful when you "import" utf8-data into perl, or when |
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some external function (e.g. storing/retrieving from a database) removes |
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the utf8-flag. |
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|
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=item utf8_on scalar |
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Similar to C<utf8 scalar, 1>, but additionally returns the scalar (the |
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argument is still modified in-place). |
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|
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=item utf8_off scalar |
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|
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Similar to C<utf8 scalar, 0>, but additionally returns the scalar (the |
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argument is still modified in-place). |
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|
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=item utf8_valid scalar [Perl 5.7] |
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Returns true if the bytes inside the scalar form a valid utf8 string, |
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false otherwise (the check is independent of the actual encoding perl |
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thinks the string is in). |
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|
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=item utf8_upgrade scalar |
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Convert the string content of the scalar in-place to its UTF8-encoded form |
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(and also returns it). |
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|
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=item utf8_downgrade scalar[, fail_ok=0] |
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Attempt to convert the string content of the scalar from UTF8-encoded to |
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ISO-8859-1. This may not be possible if the string contains characters |
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that cannot be represented in a single byte; if this is the case, it |
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leaves the scalar unchanged and either returns false or, if C<fail_ok> is |
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not true (the default), croaks. |
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|
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=item utf8_encode scalar |
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Convert the string value of the scalar to UTF8-encoded, but then turn off |
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the C<SvUTF8> flag so that it looks like bytes to perl again. (Might be |
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removed in future versions). |
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|
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=item utf8_length scalar |
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Returns the number of characters in the string, counting wide UTF8 |
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characters as a single character, independent of wether the scalar is |
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marked as containing bytes or mulitbyte characters. |
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|
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=item unmagic scalar |
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Removes magic from the scalar. |
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=item weaken scalar |
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Weaken a reference. (See also L<WeakRef>). |
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=item taint scalar |
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Taint the scalar. |
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=item tainted scalar |
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returns true when the scalar is tainted, false otherwise. |
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=item untaint scalar, type |
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Remove the specified magic from the scalar |
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(DANGEROUS!), L<perlguts>. L<Untaint>, for a similar but different |
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interface. |
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|
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=item grow scalar, newlen |
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|
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Sets the memory area used for the scalar to the given length, if the |
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current length is less than the new value. This does not affect the |
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contents of the scalar, but is only useful to "pre-allocate" memory space |
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if you know the scalar will grow. The return value is the modified scalar |
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(the scalar is modified in-place). |
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|
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=cut |
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|
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1; |
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|
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=back |
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=head2 CANDIDATES FOR FUTURE RELEASES |
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|
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The following API functions (L<perlapi>) are considered for future |
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inclusion in this module If you want them, write me. |
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|
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sv_upgrade |
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sv_pvn_force |
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sv_pvutf8n_force |
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the sv2xx family |
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|
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=head1 AUTHOR |
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|
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Marc Lehmann <pcg@goof.com> |
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http://www.goof.com/pcg/marc/ |
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|
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=cut |
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|
