composerx 0.0.16

Never write the same regexp again, ...ok, ...almost!

In less than 1KB composerx aims to help to:

1. define a specific RegExp (once)
2. reuse defined ones to define another RegExp
3. go back to 1 or 2

const crx = require('composerx');

crx.add('1-31', /^(([1-9])|([1-2]\d)|(3[01]))$/);
crx.add('3letters',  /^([a-z]{3})$/i);
crx.compose(
    'myComposedRx',
    'cx(1-31)|cx(3letters)',
);


const res1 = crx.match('myComposedRx', '3'),
    res2 = crx.match('myComposedRx', 'abf');

console.log(crx.get('myComposedRx').source)


console.log({
    res1,
    // ['3', '3', '3', '3', undefined, ...]
    
    res2 
    // ['abf', undefined, undefined, undefined, undefined, 'abf', ....]
    
    myComposedRx: crx.get('myComposedRx').source
    // (^(([1-9])|([1-2]\d)|(3[01]))$|^([a-z]{3})$)
});

API

All methods are static, thus no need for instances.
All chainable methods show a 🔗

composerx.add(String name, RegExp rx)

Adds a named element to the set of the reusable ones.

• throws
  when name is not a truthy string
  when rx is not a RegExp
• overrides
  in case an element with that name exists already

returns: 🔗

composerx.get(String name)

Retrives an element when existing, null otherwise.

• throws
  when name is not a truthy string.

returns: the named element if it exists, undefined otherwise

composerx.remove(String name)

Removes an existing element

• throws
  when name is not a string or is an empty string.
• no effect
  when the element is not found.

returns: 🔗

composerx.compose(String name, String tpl)

Creates a new the elements named name (or overrides an existing one) using the template passed to create the new RegExp using previously added elements.
To use an existing element add for it a placeholder inside the tpl parameter (see the example above).
The placeholder for element named myRx1 is cx(myRx1).

• throws
  when name or tpl is not a string or is empty string.

returns: 🔗

composerx.match(String name, String search, {definedOnly = false})

Run a match of the search against the elements named name

• throws
  when name is not a string or is empty string.
  when search is not string.

• options.definedOnly: when passed as true all undefined will be filtered out from the resulting array

returns: the rx match output or undefined when the element does not exists

composerx.test(String name, String search, {definedOnly = false})

Run a test of the search against the elements named name

• throws
  when name is not a string or is empty string.
  when search is not string.

returns: Boolean

composerx.clear()

Removes all stored elements.

returns: 🔗