nv-string-cursor v1.0.5

nv-string-cursor

• nv-string-cursor
• avoid big str copy during tokenize

install

• npm install nv-string-cursor

usage

example

str cursor

const {Cache} = require("nv-string-cursor")

var cache = new Cache();
cache.push_pos(0,2);
cache.push_str("def\tghi");
cache.push_pos(12,15);

> cache
Cache(3) [
  _Pos { type: 0, str: '', si: 0, ei: 2 },
  _Str { type: 1, str: 'def\tghi', si: -1, ei: -1 },
  _Pos { type: 0, str: '', si: 12, ei: 15 }
]
>
> cache.take(s)
'abdef\tghijkl'
>
> cache
Cache(0) []
>

var cache = new Cache();
cache.push_pos(0);
> cache
Cache(1) [ _Pos { type: 0, str: '', si: 0, ei: -1 } ]

cache.ei = 3

> cache
Cache(1) [ _Pos { type: 0, str: '', si: 0, ei: 3 } ]
>

cache.push_str("def\tghi");
cache.push_pos(12);

> cache
Cache(3) [
  _Pos { type: 0, str: '', si: 0, ei: 3 },
  _Str { type: 1, str: 'def\tghi', si: -1, ei: -1 },
  _Pos { type: 0, str: '', si: 12, ei: -1 }
]
>

cache.ei=15
> cache.take(s)
'abcdef\tghijkl'

char cursor

var s = "~🚢~"

var cursor = new Cursor()
/*Cursor { prev: -1, curr: 0 }*/

> cursor.forward(s)
1
> cursor
Cursor { prev: 0, curr: 1 }
>

> cursor.forward(s)
3
> cursor
Cursor { prev: 1, curr: 3 }
>
> cursor.ch(s)
'🚢'
>
> cursor.forward(s)
4
> cursor
Cursor { prev: 3, curr: 4 }
>
> cursor.forward(s)
undefined
>  cursor.ch(s)
''
> cursor
Cursor { prev: 4, curr: undefined }
>
> cursor.is_eof()
true
>

METHODS

Cache

     cache.ei                    
     cache.lst                   
     cache.push_pos              
     cache.push_str              
     cache.take
     cache.clear

Cursor

cursor.back                //only once ,and after back cant take ch
cursor.ch
cursor.forward
cursor.is_eof
cursor.curr
cursor.prev

LICENSE

• ISC