incstr

Increment strings or generate sequential string ids in node.js or browser

Usage

$3



nextStr = incstr(str,

                 [alphabet=incstr.alphabet],

                 [numberlike=incstr.numberlike])

str

 - string to increment;

-

alphabet - alphabet to use (default 'A..Za..z0..9'

);

-

numberlike - 'BA' after '9' instead of 'AA'(default false

);

- default

alphabet can be set through incstr.alphabet

;

- default value for

numberlike can be set through incstr.numberlike

;

- works with strings of any length.



$3



nextId = incstr.idGenerator(options)

id = nextId() // real generator would be too bulky "nextId.next().value"



Possible options:

-

options.lastId

;

-

options.alphabet

;

-

options.numberlike

;

-

options.prefix

;

-

options.suffix

lastId can also be accessed later through nextId.lastId

 property.



Note that

nextId() is much faster than incstr()

 and safer because it verifies uniqueness of chars in the alphabet.



Examples

Pass a string to increment using default alphabet:



let i = incstr() // "A"

i = incstr(i) // "B"

...

i = incstr(i) // "9"

i = incstr(i) // "AA"

i = incstr(i) // "AB"





Pass a string and an alphabet to use:



incstr("ccc", "abc") // "aaaa"

incstr("cc", "ab") // throws ('c' is not in alphabet 'ab')

incstr("0", "01") // "1"

incstr("1", "01") // "00", note NOT "10"

incstr("1", "01", true) // "10", numberlike increment





Generate ids:



const nextId = incstr.idGenerator()

id1 = nextId() // 'A'

id2 = nextId() // 'B'



const nextId = incstr.idGenerator({alphabet:'ab', prefix:'id_', suffix:''})

nextId() // 'id_a'

nextId() // 'id_b'

nextId() // 'id_aa'



const nextId = incstr.idGenerator({lastId:'cc', alphabet:'abc', numberlike: true})

id = nextId() // 'baa'