nv-buf-jstr-pool

• a utf-16 buffer
• for test string transfer in nvlang. normally USELESS.
• nvlang NOT support full-utf-16 AND utf-8; ONLY support ascii | latin-1 | utf-32 | partly support utf16(without surrogate) | and-special-format-1byte-str: /<ascii + 256-chinese-character/>

install

• npm install nv-buf-jstr-pool

splitted

usage

  const { creat }   = require("nv-buf-jstr-pool");

example

creat

      creat(ab:ArrayBuffer, from_offset_at_ab:Uint, byte_length:Uint, is_le=true ) : Spool


			var ab = new ArrayBuffer(1024*1024*8);

			var s1 = "abcd"
			var s2 = "ÿ我𝑒"
			var s3 = "\b\t\n\f\r"
			var s4= "\x00\x01\x02\x03\x04\x05\x06\x07\b\t\n\x0B\f\r\x0E\x0F\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1A\x1B\x1C\x1D\x1E\x1F"

			var spool = creat(ab,1024*1024*4, 4096)

add new

    Spool'add(s:String): Uint 

			var id1 = spool.add(s1);
			var id2 = spool.add(s2);
			var id3 = spool.add(s3);
			var id4 = spool.add(s4);

	/*
	  1,2,3,4    id is always from 1, for compatible with nvlang, 0 is used as none .
	*/

		/*
		> spool.buf_str_cnt_
		4
		> spool.buf_ch16_cnt_
		45
		> spool.buf_byte_cnt_
		90
		> 
		*/

get

   Spool'get(id:Uint): String

	/* ---- slow  will be copied

	> spool.get(1)
	'abcd'
	> spool.get(2)
	'ÿ我𝑒'
	> spool.get(3)
	'\b\t\n\f\r'
	> spool.get(4)
	'\x00\x01\x02\x03\x04\x05\x06\x07\b\t\n\x0B\f\r\x0E\x0F\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1A\x1B\x1C\x1D\x1E\x1F'
	> 
	> 
	> 
	*/

set

  Spool'set(id:Uint, s:String): [Boolean,<string-reason-if-failed>| <null-if-success>]
       IF    utf16-byte-length OF the new s:String  IS <=  the-max-permiter-size(which decided by add operation) : success
       ELSE                                                                                                      :  failed


	/*  slow   u16-by-u16 to write to buf

	> spool.get_curr_sz(1)
	8
	> 

	> spool.set(1,"xyz")
	[ true, 1 ]
	> 
	> spool.get(1)               // 2*3 <=8 IF size <= the original("abcd")  can update
	'xyz'
	> 

	> spool.get_curr_sz(1)
	6
	> 

	> spool.get_max_sz(1)
	8
	> 

	spool.set(1,"vwxyz")       //   cant,  2*5 > 8 
	[ false, 'orig_str_length_not_enough' ]
	> 

	spool.set(1,"abcd")

	*/

ser

        Spool'ser(id:Uint) : Uint8Array

			/* --- fast  just read not copy
			> spool.ser(2)
			Uint8Array(8) [
			  255,   0, 17,  98,
			   53, 216, 82, 220
			]
			> 

			> (new TextDecoder("utf-16")).decode(spool.ser(2))
			'ÿ我𝑒'
			> 

			*/

others

			/*  "ÿ我𝑒"     \u00ff\u6211   "\ud835\udc52"

			> spool.get_byte_cnt(2)    // same as   .length *2
			8
			> spool.get_ch16_cnt(2)    // same as  .length
			4
			> spool.get_char_cnt(2)    // same as  Array.from(s).length
			3
			> 

			> spool.get_char_codes(2)
			[ 255, 25105, 55349, 56402 ]
			> 
			> for(let i=0;i<"ÿ我𝑒".length;++i) {console.log("ÿ我𝑒".charCodeAt(i))}
			255
			25105
			55349
			56402

			> spool.get_code_points(2)
			[ 255, 25105, 119890 ]
			> 

			> for(let ch of "ÿ我𝑒") {console.log(ch.codePointAt(0))}
			255
			25105
			119890

			*/

METHODS

	spool.add                   spool.back_store_ei_        spool.back_store_si_        spool.buf_byte_cnt_         spool.buf_ch16_cnt_         spool.buf_str_cnt_          spool.capacity_             
	spool.cursor_               spool.get                   spool.get_byte_cnt          spool.get_ch16_cnt          spool.get_char_cnt          spool.get_char_codes        spool.get_code_points       spool.get_curr_sz
	spool.get_max_sz            spool.is_le                 spool.meta_                 spool.ser                   spool.set

APIS

• creat(ab:ArrayBuffer, from_offset_at_ab:Uint, byte_length:Uint, is_le=true ) : Spool

LICENSE

• ISC