var posix = require('{%= name %}');
console.log(posix.alpha);
//=> 'A-Za-z'
The POSIX standard supports the following classes or categories of charactersh (note that classes must be defined within brackets)1:
POSIX class | Equivalent to | Matches |
---|---|---|
[:alnum:] |
[A-Za-z0-9] |
digits, uppercase and lowercase letters |
[:alpha:] |
[A-Za-z] |
upper- and lowercase letters |
[:ascii:] |
[\x00-\x7F] |
ASCII characters |
[:blank:] |
[ \t] |
space and TAB characters only |
[:cntrl:] |
[\x00-\x1F\x7F] |
Control characters |
[:digit:] |
[0-9] |
digits |
[:graph:] |
[^ [:cntrl:]] |
graphic characters (all characters which have graphic representation) |
[:lower:] |
[a-z] |
lowercase letters |
[:print:] |
[[:graph] ] |
graphic characters and space |
[:punct:] |
``[-!"#$%&'()*+,./:;<=>?@[]^_`{ | }~]`` |
[:space:] |
[ \t\n\r\f\v] |
all blank (whitespace) characters, including spaces, tabs, new lines, carriage returns, form feeds, and vertical tabs |
[:upper:] |
[A-Z] |
uppercase letters |
[:word:] |
[A-Za-z0-9_] |
word characters |
[:xdigit:] |
[0-9A-Fa-f] |
hexadecimal digits |
a[[:digit:]]b
matchesa0b
,a1b
, ...,a9b
.a[:digit:]b
is invalid, character classes must be enclosed in brackets[[:digit:]abc]
matches any digit, as well asa
,b
, andc
.[abc[:digit:]]
is the same as the previous, matching any digit, as well asa
,b
, andc
[^ABZ[:lower:]]
matches any character except lowercase letters,A
,B
, andZ
.
Footnotes
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table and examples are based on the WikiBooks page for Regular Expressions/POSIX Basic Regular Expressions, which is available under the Creative Commons Attribution-ShareAlike License. ↩