|
|
| |
Unicode::Normalize(3) |
Perl Programmers Reference Guide |
Unicode::Normalize(3) |
Unicode::Normalize - Unicode Normalization Forms
(1) using function names exported by default:
use Unicode::Normalize;
$NFD_string = NFD($string); # Normalization Form D
$NFC_string = NFC($string); # Normalization Form C
$NFKD_string = NFKD($string); # Normalization Form KD
$NFKC_string = NFKC($string); # Normalization Form KC
(2) using function names exported on request:
use Unicode::Normalize 'normalize';
$NFD_string = normalize('D', $string); # Normalization Form D
$NFC_string = normalize('C', $string); # Normalization Form C
$NFKD_string = normalize('KD', $string); # Normalization Form KD
$NFKC_string = normalize('KC', $string); # Normalization Form KC
Parameters:
$string is used as a string under
character semantics (see perlunicode).
$code_point should be an unsigned integer
representing a Unicode code point.
Note: Between XSUB and pure Perl, there is an incompatibility
about the interpretation of $code_point as a decimal
number. XSUB converts $code_point to an unsigned
integer, but pure Perl does not. Do not use a floating point nor a negative
sign in $code_point.
- "$NFD_string = NFD($string)"
- It returns the Normalization Form D (formed by canonical
decomposition).
- "$NFC_string = NFC($string)"
- It returns the Normalization Form C (formed by canonical decomposition
followed by canonical composition).
- "$NFKD_string = NFKD($string)"
- It returns the Normalization Form KD (formed by compatibility
decomposition).
- "$NFKC_string = NFKC($string)"
- It returns the Normalization Form KC (formed by compatibility
decomposition followed by canonical composition).
- "$FCD_string = FCD($string)"
- If the given string is in FCD ("Fast C or D" form; cf. UTN #5),
it returns the string without modification; otherwise it returns an FCD
string.
Note: FCD is not always unique, then plural forms may be
equivalent each other. "FCD()" will
return one of these equivalent forms.
- "$FCC_string = FCC($string)"
- It returns the FCC form ("Fast C Contiguous"; cf. UTN #5).
Note: FCC is unique, as well as four normalization forms
(NF*).
- "$normalized_string = normalize($form_name, $string)"
- It returns the normalization form of $form_name.
As $form_name, one of the following
names must be given.
'C' or 'NFC' for Normalization Form C (UAX #15)
'D' or 'NFD' for Normalization Form D (UAX #15)
'KC' or 'NFKC' for Normalization Form KC (UAX #15)
'KD' or 'NFKD' for Normalization Form KD (UAX #15)
'FCD' for "Fast C or D" Form (UTN #5)
'FCC' for "Fast C Contiguous" (UTN #5)
- "$decomposed_string = decompose($string [,
$useCompatMapping])"
- It returns the concatenation of the decomposition of each character in the
string.
If the second parameter (a boolean) is omitted or false, the
decomposition is canonical decomposition; if the second parameter (a
boolean) is true, the decomposition is compatibility decomposition.
The string returned is not always in NFD/NFKD. Reordering may
be required.
$NFD_string = reorder(decompose($string)); # eq. to NFD()
$NFKD_string = reorder(decompose($string, TRUE)); # eq. to NFKD()
- "$reordered_string = reorder($string)"
- It returns the result of reordering the combining characters according to
Canonical Ordering Behavior.
For example, when you have a list of NFD/NFKD strings, you can
get the concatenated NFD/NFKD string from them, by saying
$concat_NFD = reorder(join '', @NFD_strings);
$concat_NFKD = reorder(join '', @NFKD_strings);
- "$composed_string = compose($string)"
- It returns the result of canonical composition without applying any
decomposition.
For example, when you have a NFD/NFKD string, you can get its
NFC/NFKC string, by saying
$NFC_string = compose($NFD_string);
$NFKC_string = compose($NFKD_string);
- "($processed, $unprocessed) =
splitOnLastStarter($normalized)"
- It returns two strings: the first one, $processed,
is a part before the last starter, and the second one,
$unprocessed is another part after the first part.
A starter is a character having a combining class of zero (see UAX #15).
Note that $processed may be empty
(when $normalized contains no starter or starts
with the last starter), and then $unprocessed
should be equal to the entire $normalized.
When you have a $normalized string and
an $unnormalized string following it, a simple
concatenation is wrong:
$concat = $normalized . normalize($form, $unnormalized); # wrong!
Instead of it, do like this:
($processed, $unprocessed) = splitOnLastStarter($normalized);
$concat = $processed . normalize($form,$unprocessed.$unnormalized);
"splitOnLastStarter()"
should be called with a pre-normalized parameter
$normalized, that is in the same form as
$form you want.
If you have an array of @string that
should be concatenated and then normalized, you can do like this:
my $result = "";
my $unproc = "";
foreach my $str (@string) {
$unproc .= $str;
my $n = normalize($form, $unproc);
my($p, $u) = splitOnLastStarter($n);
$result .= $p;
$unproc = $u;
}
$result .= $unproc;
# instead of normalize($form, join('', @string))
- "$processed = normalize_partial($form, $unprocessed)"
- A wrapper for the combination of
"normalize()" and
"splitOnLastStarter()". Note that
$unprocessed will be modified as a side-effect.
If you have an array of @string that
should be concatenated and then normalized, you can do like this:
my $result = "";
my $unproc = "";
foreach my $str (@string) {
$unproc .= $str;
$result .= normalize_partial($form, $unproc);
}
$result .= $unproc;
# instead of normalize($form, join('', @string))
- "$processed = NFD_partial($unprocessed)"
- It does like "normalize_partial('NFD',
$unprocessed)". Note that $unprocessed
will be modified as a side-effect.
- "$processed = NFC_partial($unprocessed)"
- It does like "normalize_partial('NFC',
$unprocessed)". Note that $unprocessed
will be modified as a side-effect.
- "$processed = NFKD_partial($unprocessed)"
- It does like "normalize_partial('NFKD',
$unprocessed)". Note that $unprocessed
will be modified as a side-effect.
- "$processed = NFKC_partial($unprocessed)"
- It does like "normalize_partial('NFKC',
$unprocessed)". Note that $unprocessed
will be modified as a side-effect.
(see Annex 8, UAX #15; and DerivedNormalizationProps.txt)
The following functions check whether the string is in that
normalization form.
The result returned will be one of the following:
YES The string is in that normalization form.
NO The string is not in that normalization form.
MAYBE Dubious. Maybe yes, maybe no.
- "$result = checkNFD($string)"
- It returns true (1) if
"YES"; false
("empty string") if
"NO".
- "$result = checkNFC($string)"
- It returns true (1) if
"YES"; false
("empty string") if
"NO";
"undef" if
"MAYBE".
- "$result = checkNFKD($string)"
- It returns true (1) if
"YES"; false
("empty string") if
"NO".
- "$result = checkNFKC($string)"
- It returns true (1) if
"YES"; false
("empty string") if
"NO";
"undef" if
"MAYBE".
- "$result = checkFCD($string)"
- It returns true (1) if
"YES"; false
("empty string") if
"NO".
- "$result = checkFCC($string)"
- It returns true (1) if
"YES"; false
("empty string") if
"NO";
"undef" if
"MAYBE".
Note: If a string is not in FCD, it must not be in FCC. So
"checkFCC($not_FCD_string)" should
return "NO".
- "$result = check($form_name, $string)"
- It returns true (1) if
"YES"; false
("empty string") if
"NO";
"undef" if
"MAYBE".
As $form_name, one of the following
names must be given.
'C' or 'NFC' for Normalization Form C (UAX #15)
'D' or 'NFD' for Normalization Form D (UAX #15)
'KC' or 'NFKC' for Normalization Form KC (UAX #15)
'KD' or 'NFKD' for Normalization Form KD (UAX #15)
'FCD' for "Fast C or D" Form (UTN #5)
'FCC' for "Fast C Contiguous" (UTN #5)
Note
In the cases of NFD, NFKD, and FCD, the answer must be either
"YES" or
"NO". The answer
"MAYBE" may be returned in the cases of
NFC, NFKC, and FCC.
A "MAYBE" string should contain
at least one combining character or the like. For example,
"COMBINING ACUTE ACCENT" has the
MAYBE_NFC/MAYBE_NFKC property.
Both "checkNFC("A\N{COMBINING ACUTE
ACCENT}")" and
"checkNFC("B\N{COMBINING ACUTE
ACCENT}")" will return
"MAYBE".
"A\N{COMBINING ACUTE ACCENT}" is not in
NFC (its NFC is "\N{LATIN CAPITAL LETTER A WITH
ACUTE}"), while "B\N{COMBINING ACUTE
ACCENT}" is in NFC.
If you want to check exactly, compare the string with its
NFC/NFKC/FCC.
if ($string eq NFC($string)) {
# $string is exactly normalized in NFC;
} else {
# $string is not normalized in NFC;
}
if ($string eq NFKC($string)) {
# $string is exactly normalized in NFKC;
} else {
# $string is not normalized in NFKC;
}
These functions are interface of character data used internally. If you want
only to get Unicode normalization forms, you don't need call them yourself.
- "$canonical_decomposition = getCanon($code_point)"
- If the character is canonically decomposable (including Hangul Syllables),
it returns the (full) canonical decomposition as a string. Otherwise it
returns "undef".
Note: According to the Unicode standard, the canonical
decomposition of the character that is not canonically decomposable is
same as the character itself.
- "$compatibility_decomposition = getCompat($code_point)"
- If the character is compatibility decomposable (including Hangul
Syllables), it returns the (full) compatibility decomposition as a string.
Otherwise it returns "undef".
Note: According to the Unicode standard, the
compatibility decomposition of the character that is not compatibility
decomposable is same as the character itself.
- "$code_point_composite = getComposite($code_point_here,
$code_point_next)"
- If two characters here and next (as code points) are composable (including
Hangul Jamo/Syllables and Composition Exclusions), it returns the code
point of the composite.
If they are not composable, it returns
"undef".
- "$combining_class = getCombinClass($code_point)"
- It returns the combining class (as an integer) of the character.
- "$may_be_composed_with_prev_char = isComp2nd($code_point)"
- It returns a boolean whether the character of the specified codepoint may
be composed with the previous one in a certain composition (including
Hangul Compositions, but excluding Composition Exclusions and Non-Starter
Decompositions).
- "$is_exclusion = isExclusion($code_point)"
- It returns a boolean whether the code point is a composition
exclusion.
- "$is_singleton = isSingleton($code_point)"
- It returns a boolean whether the code point is a singleton
- "$is_non_starter_decomposition =
isNonStDecomp($code_point)"
- It returns a boolean whether the code point has Non-Starter
Decomposition.
- "$is_Full_Composition_Exclusion = isComp_Ex($code_point)"
- It returns a boolean of the derived property Comp_Ex
(Full_Composition_Exclusion). This property is generated from Composition
Exclusions + Singletons + Non-Starter Decompositions.
- "$NFD_is_NO = isNFD_NO($code_point)"
- It returns a boolean of the derived property NFD_NO
(NFD_Quick_Check=No).
- "$NFC_is_NO = isNFC_NO($code_point)"
- It returns a boolean of the derived property NFC_NO
(NFC_Quick_Check=No).
- "$NFC_is_MAYBE = isNFC_MAYBE($code_point)"
- It returns a boolean of the derived property NFC_MAYBE
(NFC_Quick_Check=Maybe).
- "$NFKD_is_NO = isNFKD_NO($code_point)"
- It returns a boolean of the derived property NFKD_NO
(NFKD_Quick_Check=No).
- "$NFKC_is_NO = isNFKC_NO($code_point)"
- It returns a boolean of the derived property NFKC_NO
(NFKC_Quick_Check=No).
- "$NFKC_is_MAYBE = isNFKC_MAYBE($code_point)"
- It returns a boolean of the derived property NFKC_MAYBE
(NFKC_Quick_Check=Maybe).
"NFC",
"NFD",
"NFKC",
"NFKD": by default.
"normalize" and other some
functions: on request.
- Perl's version vs. Unicode version
- Since this module refers to perl core's Unicode database in the directory
/lib/unicore (or formerly /lib/unicode), the Unicode version
of normalization implemented by this module depends on what has been
compiled into your perl. The following table lists the default Unicode
version that comes with various perl versions. (It is possible to change
the Unicode version in any perl version to be any earlier Unicode version,
so one could cause Unicode 3.2 to be used in any perl version starting
with 5.8.0. Read $Config{privlib}/unicore/README.perl
for details.
perl's version implemented Unicode version
5.6.1 3.0.1
5.7.2 3.1.0
5.7.3 3.1.1 (normalization is same as 3.1.0)
5.8.0 3.2.0
5.8.1-5.8.3 4.0.0
5.8.4-5.8.6 4.0.1 (normalization is same as 4.0.0)
5.8.7-5.8.8 4.1.0
5.10.0 5.0.0
5.8.9, 5.10.1 5.1.0
5.12.x 5.2.0
5.14.x 6.0.0
5.16.x 6.1.0
5.18.x 6.2.0
5.20.x 6.3.0
5.22.x 7.0.0
- Correction of decomposition mapping
- In older Unicode versions, a small number of characters (all of which are
CJK compatibility ideographs as far as they have been found) may have an
erroneous decomposition mapping (see NormalizationCorrections.txt).
Anyhow, this module will neither refer to
NormalizationCorrections.txt nor provide any specific version of
normalization. Therefore this module running on an older perl with an
older Unicode database may use the erroneous decomposition mapping blindly
conforming to the Unicode database.
- Revised definition of canonical composition
- In Unicode 4.1.0, the definition D2 of canonical composition (which
affects NFC and NFKC) has been changed (see Public Review Issue #29 and
recent UAX #15). This module has used the newer definition since the
version 0.07 (Oct 31, 2001). This module will not support the
normalization according to the older definition, even if the Unicode
version implemented by perl is lower than 4.1.0.
SADAHIRO Tomoyuki <SADAHIRO@cpan.org>
Currently maintained by <perl5-porters@perl.org>
Copyright(C) 2001-2012, SADAHIRO Tomoyuki. Japan. All rights
reserved.
This module is free software; you can redistribute it and/or modify it under the
same terms as Perl itself.
- <http://www.unicode.org/reports/tr15/>
- Unicode Normalization Forms - UAX #15
- <http://www.unicode.org/Public/UNIDATA/CompositionExclusions.txt>
- Composition Exclusion Table
- <http://www.unicode.org/Public/UNIDATA/DerivedNormalizationProps.txt>
- Derived Normalization Properties
- <http://www.unicode.org/Public/UNIDATA/NormalizationCorrections.txt>
- Normalization Corrections
- <http://www.unicode.org/review/pr-29.html>
- Public Review Issue #29: Normalization Issue
- <http://www.unicode.org/notes/tn5/>
- Canonical Equivalence in Applications - UTN #5
Visit the GSP FreeBSD Man Page Interface. Output converted with ManDoc. |