ilib-ctype

Common utility functions for ilib. iLib is a cross-engine library of internationalization (i18n) classes written in pure JS

Usage no npm install needed!

<script type="module">
  import ilibCtype from 'https://cdn.skypack.dev/ilib-ctype';
</script>

README

ilib-common

Various utility classes for the ilib packages.

Installation

npm install ilib-ctype

or

yarn add ilib-ctype

CType Functions

The CType functions are modeled after the posix ctype functions for C/C++. The data for all of the CType functions are derived from the Unicode Character Database so that they can be called with any character in Unicode. (Many posix implementations do not support Unicode!)

Because Javascript does not have an intrinsic character type, the arguments for these functions are strings. Only the very first character in the string is examined to determine the output of the function. The rest of the string is ignored.

The functions are as follows:

  • isAlnum - is the character alpha numeric?
  • isAlpha - is the character alphabetic?
  • isAscii - is the character part of the ASCII subset?
  • isBlank - is the character blank?
  • isCntrl - is the character a control character?
  • isDigit - is the character a digit?
  • isGraph - is the character a graphic character?
  • isIdeo - is the character an ideographic (Asian) character?
  • isLower - is the character lower-case? For scripts that do not have the concept of cases, this always returns true.
  • isPrint - is the character printable on the screen?
  • isPunct - is the character a punctuation character?
  • isScript - does the given character belong to the named script?
  • isSpace - is the character a whitespace character?
  • isUpper - is the character upper-case? For scripts that do not have the concept of case, this always returns true.
  • isXdigit - is this character a hexadecimal digit?

Additionally, there is a withinRange() function which returns true if the given character is within the named Unicode range.

import { withinRange } from 'ilib-ctype';

console.log(withinRange("\uFE2A", "HalfMarks")); // prints true

Using the CType Functions

All of the functions are exported from the package in general. Here is an example of how you would use the isAlpha function.

import { isAlpha } from "ilib-ctype";

console.log(isAlpha("a"));   // prints true
console.log(isAlpha("3"));   // prints false

If you are using ilib-ctype with webpack or any other packaging tool and do not want to include the entire package with all of its associated data when you only need just one function, then you can minimize your footprint by importing that function directly:

import isDigit from 'ilib-ctype/lib/isDigit';

console.log(isDigit("2")); // prints true

That will only drag in the isDigit function, the withinRange function, and the ctype_n.json file (2K compressed). All the rest of the data will not be dragged in to your package.

License

Copyright © 2021, JEDLSoft

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

See the License for the specific language governing permissions and limitations under the License.

Release Notes

v1.0.0

  • initial version
  • copied from ilib 14.8.0