uctools 1.3.0

Unicode tools.

Tools for showing information about unicode characters (UTF-8) and performing normalization.

Copyright ® 2018, Luís Gomes <[e-mail]>.

The following command line tools are provided:

ucinfo

writes on stdout the name of each unicode character read from stdin

ucenum

enumerates on stdout all unicode characters of a chosen category

ucnorm

applies a standard unicode normalization (NFC, NFKC, NFD or NFKD)

ucinfo

The ucinfo tool reads UTF-8 text from stdin and writes to stdout information about each character, one per line. The output has 5 tab-separated columns:

1. the character itself, if printable, or an escaped representation of it

2. the decimal codepoint of the character

3. the number of bytes that the character occupies

4. the Unicode category of the character

5. the Unicode name of the character

ucenum

The ucenum tool takes a category abbreviation as argument and outputs a list

of all characters belonging to that category. The categories are:

L

Letter

Lu

Letter, Uppercase

Ll

Letter, Lowercase

Lt

Letter, Titlecase

Lm

Letter, Modifier

Lo

Letter, Other

M

Mark

Mn

Mark, Nonspacing

Mc

Mark, Spacing Combining

Me

Mark, Enclosing

N

Number

Nd

Number, Decimal Digit

Nl

Number, Letter

No

Number, Other

P

Punctuation

Pc

Punctuation, Connector

Pd

Punctuation, Dash

Ps

Punctuation, Open

Pe

Punctuation, Close

Pi

Punctuation, Initial quote (may behave like Ps or Pe depending on usage)

Pf

Punctuation, Final quote (may behave like Ps or Pe depending on usage)

Po

Punctuation, Other

S

Symbol

Sm

Symbol, Math

Sc

Symbol, Currency

Sk

Symbol, Modifier

So

Symbol, Other

Z

Separator

Zs

Separator, Space

Zl

Separator, Line

Zp

Separator, Paragraph

C

Other

Cc

Other, Control

Cf

Other, Format

Cs

Other, Surrogate

Co

Other, Private Use

Cn

Other, Not Assigned

ucnorm

This program reads UTF-8 text from stdin and writes it to stdout after applying the specified normalization algorithm.

The Unicode standard defines various normalization forms of a Unicode string, based on the definition of canonical equivalence and compatibility equivalence. In Unicode, several characters can be expressed in various way. For example, the character U+00C7 (LATIN CAPITAL LETTER C WITH CEDILLA) can also be expressed as the sequence U+0043 (LATIN CAPITAL LETTER C) U+0327 (COMBINING CEDILLA).

Even if two unicode strings look the same to a human reader, if one has combining characters and the other doesn’t, they may not compare equal.

For each character, there are two normal forms:

• Normal form D (NFD) is also known as canonical decomposition, and translates each character into its decomposed form.

• Normal form C (NFC) first applies a canonical decomposition, then composes pre-combined characters again.

In addition to these two forms, there are two additional normal forms based on compatibility equivalence:

• Normal form KD (NFKD) will apply the compatibility decomposition, i.e. replace all compatibility characters with their equivalents.

• Normal form KC (NFKC) first applies the compatibility decomposition, followed by the canonical composition.

Compatibility decomposition ensures that equivalent characters will compare equal (i.e. have the same codepoints). In Unicode, certain characters are supported which normally would be unified with other characters. For example, U+2160 (ROMAN NUMERAL ONE) is really the same thing as U+0049 (LATIN CAPITAL LETTER I). However, it is supported in Unicode for compatibility with existing character sets (e.g. gb2312).

This program uses the normalization algorithms implemented in Python’s standard library. See: https://docs.python.org/3/library/unicodedata.html#unicodedata.normalize