package bytes

import "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"

Package bytes provide a library for working with byte or slice of bytes.

Index

Examples

Functions

func CutUntilToken 

func CutUntilToken(text, token []byte, startAt int, checkEsc bool) (cut []byte, pos int, found bool)

CutUntilToken cut text until we found token.

If token found, it will return all bytes before token, position of byte after token, and true.

If no token found, it will return false.

If checkEsc is true, token that is prefixed with escaped character ('\') will be skipped, the escape character will be removed.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	text := []byte(`\\abc \def \deg`)

	cut, pos, found := libbytes.CutUntilToken(text, nil, 0, false)
	fmt.Printf("'%s' %d %t\n", cut, pos, found)

	cut, pos, found = libbytes.CutUntilToken(text, []byte("def"), 0, false)
	fmt.Printf("'%s' %d %t\n", cut, pos, found)

	cut, pos, found = libbytes.CutUntilToken(text, []byte("def"), 0, true)
	fmt.Printf("'%s' %d %t\n", cut, pos, found)

	cut, pos, found = libbytes.CutUntilToken(text, []byte("ef"), -1, true)
	fmt.Printf("'%s' %d %t\n", cut, pos, found)

	cut, pos, found = libbytes.CutUntilToken(text, []byte("hi"), 0, true)
	fmt.Printf("'%s' %d %t\n", cut, pos, found)

}

Output:

'\\abc \def \deg' -1 false
'\\abc \' 10 true
'\abc def \deg' 15 false
'\abc \d' 10 true
'\abc \def \deg' 15 false

func EncloseRemove 

func EncloseRemove(text, leftToken, rightToken []byte) (cut []byte, found bool)

EncloseRemove given a text, find the leftToken and rightToken and cut the content in between them and return it with status true. Keep doing it until no more leftToken and rightToken found.

If no leftToken or rightToken is found, it will return text as is and false.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	text := []byte(`[[ A ]]-[[ B ]] C`)

	got, isCut := libbytes.EncloseRemove(text, []byte("[["), []byte("]]"))
	fmt.Printf("'%s' %t\n", got, isCut)

	got, isCut = libbytes.EncloseRemove(text, []byte("[["), []byte("}}"))
	fmt.Printf("'%s' %t\n", got, isCut)

	text = []byte(`// Copyright 2016-2018 "Shulhan <ms@kilabit.info>". All rights reserved.`)

	got, isCut = libbytes.EncloseRemove(text, []byte("<"), []byte(">"))
	fmt.Printf("'%s' %t\n", got, isCut)

	got, isCut = libbytes.EncloseRemove(text, []byte(`"`), []byte(`"`))
	fmt.Printf("'%s' %t\n", got, isCut)

	got, isCut = libbytes.EncloseRemove(text, []byte(`/`), []byte(`/`))
	fmt.Printf("'%s' %t\n", got, isCut)

	text = []byte(`/* TEST */`)

	got, isCut = libbytes.EncloseRemove(text, []byte(`/*`), []byte(`*/`))
	fmt.Printf("'%s' %t\n", got, isCut)

}

Output:

'- C' true
'[[ A ]]-[[ B ]] C' false
'// Copyright 2016-2018 "Shulhan ". All rights reserved.' true
'// Copyright 2016-2018 . All rights reserved.' true
' Copyright 2016-2018 "Shulhan <ms@kilabit.info>". All rights reserved.' true
'' true

func EncloseToken 

func EncloseToken(text, token, leftcap, rightcap []byte) (
	newtext []byte,
	found bool,
)

EncloseToken find "token" in "text" and enclose it with bytes from "leftcap" and "rightcap". If at least one token found, it will return modified text with true status. If no token is found, it will return the same text with false status.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	text := []byte(`// Copyright 2016-2018 "Shulhan <ms@kilabit.info>". All rights reserved.`)

	got, isChanged := libbytes.EncloseToken(text, []byte(`"`), []byte(`\`), []byte(`_`))
	fmt.Printf("%t '%s'\n", isChanged, got)

	got, isChanged = libbytes.EncloseToken(text, []byte(`_`), []byte(`-`), []byte(`-`))
	fmt.Printf("%t '%s'\n", isChanged, got)

	got, isChanged = libbytes.EncloseToken(text, []byte(`/`), []byte(`\`), nil)
	fmt.Printf("%t '%s'\n", isChanged, got)

	got, isChanged = libbytes.EncloseToken(text, []byte(`<`), []byte(`<`), []byte(` `))
	fmt.Printf("%t '%s'\n", isChanged, got)

}

Output:

true '// Copyright 2016-2018 \"_Shulhan <ms@kilabit.info>\"_. All rights reserved.'
false '// Copyright 2016-2018 "Shulhan <ms@kilabit.info>". All rights reserved.'
true '\/\/ Copyright 2016-2018 "Shulhan <ms@kilabit.info>". All rights reserved.'
true '// Copyright 2016-2018 "Shulhan << ms@kilabit.info>". All rights reserved.'

func InReplace 

func InReplace(text, allowed []byte, c byte) []byte

InReplace replace any characters in "text" that is not in "allowed" with character "c". The replacement occur inside the "text" backing storage, which means the passed "text" will changes and returned.

Example

Code:play  

package main

import (
	"fmt"

	"git.sr.ht/~shulhan/pakakeh.go/lib/ascii"
	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	text := libbytes.InReplace([]byte{}, []byte(ascii.LettersNumber), '_')
	fmt.Printf("%q\n", text)

	text = libbytes.InReplace([]byte("/a/b/c"), []byte(ascii.LettersNumber), '_')
	fmt.Printf("%q\n", text)

	_ = libbytes.InReplace(text, []byte(ascii.LettersNumber), '/')
	fmt.Printf("%q\n", text)

}

Output:

""
"_a_b_c"
"/a/b/c"

func Indexes 

func Indexes(text, token []byte) (idxs []int)

Indexes returns the index of the all instance of "token" in "text", or nil if no "token" found.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	fmt.Println(libbytes.Indexes([]byte(""), []byte("moo")))
	fmt.Println(libbytes.Indexes([]byte("moo moomoo"), []byte{}))
	fmt.Println(libbytes.Indexes([]byte("moo moomoo"), []byte("moo")))
}

Output:

[]
[]
[0 4 7]

func IsTokenAt 

func IsTokenAt(text, token []byte, p int) bool

IsTokenAt return true if `text` at index `p` match with `token`, otherwise it will return false. Empty token always return false.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	text := []byte("Hello, world")
	tokenWorld := []byte("world")
	tokenWorlds := []byte("worlds")
	tokenEmpty := []byte{}

	fmt.Printf("%t\n", libbytes.IsTokenAt(text, tokenEmpty, 6))
	fmt.Printf("%t\n", libbytes.IsTokenAt(text, tokenWorld, -1))
	fmt.Printf("%t\n", libbytes.IsTokenAt(text, tokenWorld, 6))
	fmt.Printf("%t\n", libbytes.IsTokenAt(text, tokenWorld, 7))
	fmt.Printf("%t\n", libbytes.IsTokenAt(text, tokenWorld, 8))
	fmt.Printf("%t\n", libbytes.IsTokenAt(text, tokenWorlds, 8))
}

Output:

false
false
false
true
false
false

func MergeSpaces 

func MergeSpaces(in []byte) (out []byte)

MergeSpaces convert sequences of white spaces into single space ' '.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	fmt.Printf("%s\n", libbytes.MergeSpaces([]byte("")))
	fmt.Printf("%s\n", libbytes.MergeSpaces([]byte(" \t\v\r\n\r\n\fa \t\v\r\n\r\n\f")))
}

Output:

 a

func ReadHexByte 

func ReadHexByte(data []byte, x int) (b byte, ok bool)

ReadHexByte read two hexadecimal characters from "data" start from index "x" and convert them to byte. It will return the byte and true if its read exactly two hexadecimal characters, otherwise it will return 0 and false.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	fmt.Println(libbytes.ReadHexByte([]byte{}, 0))
	fmt.Println(libbytes.ReadHexByte([]byte("x0"), 0))
	fmt.Println(libbytes.ReadHexByte([]byte("00"), 0))
	fmt.Println(libbytes.ReadHexByte([]byte("01"), 0))
	fmt.Println(libbytes.ReadHexByte([]byte("10"), 0))
	fmt.Println(libbytes.ReadHexByte([]byte("1A"), 0))
	fmt.Println(libbytes.ReadHexByte([]byte("1a"), 0))
	fmt.Println(libbytes.ReadHexByte([]byte("1a"), -1))
}

Output:

0 false
0 false
0 true
1 true
16 true
26 true
26 true
0 false

func RemoveSpaces 

func RemoveSpaces(in []byte) (out []byte)

RemoveSpaces remove all spaces from input in.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		in  = []byte(" a\nb\tc d\r")
		out = libbytes.RemoveSpaces(in)
	)

	fmt.Printf("%s\n", out)

}

Output:

abcd

func SkipAfterToken 

func SkipAfterToken(text, token []byte, startAt int, checkEsc bool) (int, bool)

SkipAfterToken skip all bytes until matched "token" is found and return the index after the token and boolean true.

If "checkEsc" is true, token that is prefixed with escaped character '\' will be considered as non-match token.

If no token found it will return -1 and boolean false.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	text := []byte(`abc \def ghi`)

	fmt.Println(libbytes.SkipAfterToken(text, []byte("def"), -1, false))
	fmt.Println(libbytes.SkipAfterToken(text, []byte("def"), 0, true))
	fmt.Println(libbytes.SkipAfterToken(text, []byte("deg"), 0, false))
	fmt.Println(libbytes.SkipAfterToken(text, []byte("deg"), 0, true))
	fmt.Println(libbytes.SkipAfterToken(text, []byte("ef"), 0, true))
	fmt.Println(libbytes.SkipAfterToken(text, []byte("hi"), 0, true))
}

Output:

8 true
-1 false
-1 false
-1 false
8 true
12 true

func SnippetByIndexes 

func SnippetByIndexes(s []byte, indexes []int, sniplen int) (snippets [][]byte)

SnippetByIndexes take snippet in between of each index with minimum snippet length. The sniplen is the length before and after index, not the length of all snippet.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	s := []byte("// Copyright 2018, Shulhan <ms@kilabit.info>. All rights reserved.")
	indexes := []int{3, 20, len(s) - 4}

	snippets := libbytes.SnippetByIndexes(s, indexes, 5)
	for _, snip := range snippets {
		fmt.Printf("%s\n", snip)
	}
}

Output:

// Copyr
18, Shulha
reserved.

func SplitEach 

func SplitEach(data []byte, n int) (chunks [][]byte)

SplitEach split the data into n number of bytes. If n is less or equal than zero, it will return the data as chunks.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var data = []byte(`Hello`)

	fmt.Printf("%s\n", libbytes.SplitEach(data, 0))
	fmt.Printf("%s\n", libbytes.SplitEach(data, 1))
	fmt.Printf("%s\n", libbytes.SplitEach(data, 2))
	fmt.Printf("%s\n", libbytes.SplitEach(data, 5))
	fmt.Printf("%s\n", libbytes.SplitEach(data, 10))
}

Output:

[Hello]
[H e l l o]
[He ll o]
[Hello]
[Hello]

func TokenFind 

func TokenFind(text, token []byte, startat int) (at int)

TokenFind return the first index of matched token in text, start at custom index. If "startat" parameter is less than 0, then it will be set to 0. If token is empty or no token found it will return -1.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	text := []byte("// Copyright 2018, Shulhan <ms@kilabit.info>. All rights reserved.")

	fmt.Println(libbytes.TokenFind(text, []byte{}, 0))
	fmt.Println(libbytes.TokenFind(text, []byte("right"), -1))
	fmt.Println(libbytes.TokenFind(text, []byte("."), 0))
	fmt.Println(libbytes.TokenFind(text, []byte("."), 42))
	fmt.Println(libbytes.TokenFind(text, []byte("."), 48))
	fmt.Println(libbytes.TokenFind(text, []byte("d."), 0))
}

Output:

-1
7
38
44
65
64

func TrimNull 

func TrimNull(in []byte) (out []byte)

TrimNull remove 0 value ("\0" or NULL in C) at leading and trailing of in.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var in = []byte{0, 'H', 'e', 'l', 'l', 'o', 0, 0}

	in = libbytes.TrimNull(in)
	fmt.Printf(`%s`, in)
}

Output:

Hello

func WordIndexes 

func WordIndexes(s []byte, word []byte) (idxs []int)

WordIndexes returns the index of the all instance of word in s as long as word is separated by space or at the beginning or end of s.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	text := []byte("moo moomoo moo")

	fmt.Println(libbytes.WordIndexes(text, []byte("mo")))
	fmt.Println(libbytes.WordIndexes(text, []byte("moo")))
	fmt.Println(libbytes.WordIndexes(text, []byte("mooo")))
}

Output:

[]
[0 11]
[]

Types

type Parser 

type Parser struct {
	// contains filtered or unexported fields
}

Parser implement tokenize parser for stream of byte using one or more delimiters as separator between token.

func NewParser 

func NewParser(content, delims []byte) (bp *Parser)

NewParser create new Parser to parse content using delims as initial delimiters.

func (*Parser) AddDelimiters 

func (bp *Parser) AddDelimiters(delims []byte)

AddDelimiters add another delimiters to the current parser.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(` a = b ; c = d `)
		delims  = []byte(`=`)
		parser  = libbytes.NewParser(content, delims)
	)

	token, d := parser.ReadNoSpace()
	fmt.Printf("%s:%c\n", token, d)

	parser.AddDelimiters([]byte{';'})
	token, d = parser.ReadNoSpace()
	fmt.Printf("%s:%c\n", token, d)

}

Output:

a:=
b:;

func (*Parser) Delimiters 

func (bp *Parser) Delimiters() []byte

Delimiters return the copy of current delimiters.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(`a=b;c=d;`)
		delims  = []byte{'=', ';'}
		parser  = libbytes.NewParser(content, delims)
	)

	fmt.Printf("%s\n", parser.Delimiters())
}

Output:

=;

func (*Parser) Read 

func (bp *Parser) Read() (token []byte, d byte)

Read read a token until one of the delimiters found. If one of delimiter match, it will return it as d. When end of content encountered, the returned token may be not empty but the d will be zero.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte("a = b; ")
		delims  = []byte{'=', ';'}
		parser  = libbytes.NewParser(content, delims)
	)

	token, c := parser.Read()
	fmt.Printf("token:'%s' c:%q\n", token, c)
	token, c = parser.Read()
	fmt.Printf("token:'%s' c:%q\n", token, c)
	token, c = parser.Read()
	fmt.Printf("token:'%s' c:%q\n", token, c)

}

Output:

token:'a ' c:'='
token:' b' c:';'
token:' ' c:'\x00'

func (*Parser) ReadLine 

func (bp *Parser) ReadLine() (line []byte, c byte)

ReadLine read until it found new line ('\n') or end of content, ignoring all delimiters. The returned line will not contain '\n'.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte("a=b;\nc=d;")
		delims  = []byte{'=', ';'}
		parser  = libbytes.NewParser(content, delims)
	)

	token, c := parser.ReadLine()
	fmt.Printf("token:%s c:%q\n", token, c)

	token, c = parser.ReadLine()
	fmt.Printf("token:%s c:%q\n", token, c)

}

Output:

token:a=b; c:'\n'
token:c=d; c:'\x00'

func (*Parser) ReadN 

func (bp *Parser) ReadN(n int) (token []byte, d byte)

ReadN read exactly n characters ignoring the delimiters. It will return the token and the character after n or 0 if end-of-content.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(`a=b;c=d;`)
		delims  = []byte{'=', ';'}
		parser  = libbytes.NewParser(content, delims)
	)

	token, c := parser.ReadN(2)
	fmt.Printf("token:%s c:%q\n", token, c)

	token, c = parser.ReadN(0)
	fmt.Printf("token:%s c:%q\n", token, c)

	token, c = parser.ReadN(10)
	fmt.Printf("token:%s c:%q\n", token, c)
}

Output:

token:a= c:'b'
token: c:'b'
token:b;c=d; c:'\x00'

func (*Parser) ReadNoSpace 

func (bp *Parser) ReadNoSpace() (token []byte, d byte)

ReadNoSpace read the next token by ignoring the leading spaces, even if its one of the delimiter. The returned token will have no trailing spaces.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(` a = b ;`)
		delims  = []byte(`=;`)
		parser  = libbytes.NewParser(content, delims)
	)

	for {
		token, d := parser.ReadNoSpace()
		fmt.Printf("%s:%q\n", token, d)
		if d == 0 {
			break
		}
	}
}

Output:

a:'='
b:';'
:'\x00'

func (*Parser) Remaining 

func (bp *Parser) Remaining() []byte

Remaining return the copy of un-parsed content.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(` a = b ;`)
		delims  = []byte(`=;`)
		parser  = libbytes.NewParser(content, delims)
	)

	token, d := parser.ReadNoSpace()
	remain := parser.Remaining()
	fmt.Printf("token:%s d:%c remain:%s\n", token, d, remain)
}

Output:

token:a d:= remain: b ;

func (*Parser) RemoveDelimiters 

func (bp *Parser) RemoveDelimiters(delims []byte)

RemoveDelimiters remove delimiters delims from current delimiters.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(` a = b ; c = d `)
		delims  = []byte(`=;`)
		parser  = libbytes.NewParser(content, delims)
	)

	token, _ := parser.ReadNoSpace()
	fmt.Printf("%s\n", token)

	parser.RemoveDelimiters([]byte{';'})
	token, _ = parser.ReadNoSpace()
	fmt.Printf("%s\n", token)

}

Output:

a
b ; c

func (*Parser) Reset 

func (bp *Parser) Reset(content, delims []byte)

Reset the Parser by setting all internal state to new content and delimiters.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(`a.b.c;`)
		delims  = []byte(`.`)
		parser  = libbytes.NewParser(content, delims)
	)

	parser.Read()
	parser.Reset(content, delims)
	remain, pos := parser.Stop()
	fmt.Printf("remain:%s pos:%d\n", remain, pos)
}

Output:

remain:a.b.c; pos:0

func (*Parser) SetDelimiters 

func (bp *Parser) SetDelimiters(delims []byte)

SetDelimiters replace the current delimiters with delims.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(`a.b.c;`)
		delims  = []byte(`.`)
		parser  = libbytes.NewParser(content, delims)
		token   []byte
	)

	token, _ = parser.Read()
	fmt.Println(string(token))

	parser.SetDelimiters([]byte(`;`))

	token, _ = parser.Read()
	fmt.Println(string(token))

}

Output:

a
b.c

func (*Parser) Skip 

func (bp *Parser) Skip() (c byte)

Skip skip parsing token until one of the delimiters found or end-of-content.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(`a = b; c = d;`)
		delims  = []byte{'=', ';'}
		parser  = libbytes.NewParser(content, delims)
		token   []byte
	)

	parser.Skip()
	token, _ = parser.ReadNoSpace()
	fmt.Println(string(token))

	parser.Skip()
	token, _ = parser.ReadNoSpace()
	fmt.Println(string(token))

	parser.Skip()
	token, _ = parser.ReadNoSpace()
	fmt.Println(string(token))

}

Output:

b
d

func (*Parser) SkipHorizontalSpaces 

func (bp *Parser) SkipHorizontalSpaces() (n int, c byte)

SkipHorizontalSpaces skip space (" "), tab ("\t"), carriage return ("\r"), and form feed ("\f") characters; and return the number of space skipped and first non-space character or 0 if it reach end-of-content.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(" \t\r\fA. \nB.")
		delims  = []byte{'.'}
		parser  = libbytes.NewParser(content, delims)
		n       int
	)

	n, _ = parser.SkipHorizontalSpaces()
	token, d := parser.Read()
	fmt.Printf("n:%d token:%s delim:%q\n", n, token, d)

	n, _ = parser.SkipHorizontalSpaces()
	token, d = parser.Read() // The token include \n.
	fmt.Printf("n:%d token:%s delim:%q\n", n, token, d)

	n, _ = parser.SkipHorizontalSpaces()
	token, d = parser.Read() // The token include \n.
	fmt.Printf("n:%d token:%s delim:%q\n", n, token, d)

}

Output:

n:4 token:A delim:'.'
n:1 token:
B delim:'.'
n:0 token: delim:'\x00'

func (*Parser) SkipLine 

func (bp *Parser) SkipLine() (c byte)

SkipLine skip all characters until new line. It will return 0 if EOF.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte("a\nb\nc\nd e\n")
		delims  = []byte("\n")
		parser  = libbytes.NewParser(content, delims)
	)

	parser.SkipLine()
	token, _ := parser.Read()
	fmt.Printf("token:'%s'\n", token)

	parser.SkipLine()
	token, _ = parser.Read()
	fmt.Printf("token:'%s'\n", token)
}

Output:

token:'b'
token:'d e'

func (*Parser) SkipN 

func (bp *Parser) SkipN(n int) (c byte)

SkipN skip exactly N characters ignoring delimiters. It will return the next character after N or 0 if it reach end-of-content.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(`a=b;c=d;`)
		delims  = []byte{'=', ';'}
		parser  = libbytes.NewParser(content, delims)
		token   []byte
		c       byte
	)

	c = parser.SkipN(2)
	fmt.Printf("Skip: %c\n", c)
	token, _ = parser.ReadNoSpace()
	fmt.Println(string(token))

	c = parser.SkipN(2)
	fmt.Printf("Skip: %c\n", c)
	token, _ = parser.ReadNoSpace()
	fmt.Println(string(token))

	_ = parser.SkipN(2)
	token, _ = parser.ReadNoSpace()
	fmt.Println(string(token))

}

Output:

Skip: b
b
Skip: d
d

func (*Parser) SkipSpaces 

func (bp *Parser) SkipSpaces() (n int, c byte)

SkipSpaces skip all spaces character (' ', '\f', '\n', '\r', '\t') and return the number of spaces skipped and first non-space character or 0 if it reach end-of-content.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(" \t\r\fA. \nB.")
		delims  = []byte{'.'}
		parser  = libbytes.NewParser(content, delims)
		n       int
	)

	n, _ = parser.SkipSpaces()
	token, d := parser.Read()
	fmt.Printf("n:%d token:%s delim:%q\n", n, token, d)

	n, _ = parser.SkipSpaces()
	token, d = parser.Read() // The token include \n.
	fmt.Printf("n:%d token:%s delim:%q\n", n, token, d)

	n, _ = parser.SkipSpaces()
	token, d = parser.Read() // The token include \n.
	fmt.Printf("n:%d token:%s delim:%q\n", n, token, d)

}

Output:

n:4 token:A delim:'.'
n:2 token:B delim:'.'
n:0 token: delim:'\x00'

func (*Parser) Stop 

func (bp *Parser) Stop() (remain []byte, pos int)

Stop the parser, return the remaining unparsed content and its last position, and then call Reset to reset the internal state back to zero.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		content = []byte(`a.b.c;`)
		delims  = []byte(`.`)
		parser  = libbytes.NewParser(content, delims)

		remain []byte
		pos    int
	)

	parser.Read()
	remain, pos = parser.Stop()
	fmt.Printf("remain:%s pos:%d\n", remain, pos)

	parser.Reset(content, []byte(`;`))
	parser.Read()
	remain, pos = parser.Stop()
	fmt.Printf("remain:%s pos:%d\n", remain, pos)

}

Output:

remain:b.c; pos:2
remain: pos:6

func (*Parser) UnreadN 

func (bp *Parser) UnreadN(n int) byte

UnreadN unread N characters and return the character its pointed to. If N greater than current position index, it will reset the read pointer index back to zero.

Example

Code:play  

package main

import (
	"fmt"

	libbytes "git.sr.ht/~shulhan/pakakeh.go/lib/bytes"
)

func main() {
	var (
		parser = libbytes.NewParser([]byte(`a,b.c/d`), []byte(`,./`))
		token  []byte
		c      byte
	)

	parser.Read()
	parser.Read()
	parser.Read()
	parser.Read() // All content should be readed now.

	c = parser.UnreadN(2) // Move the index to '/'.
	fmt.Printf("UnreadN(2): %c\n", c)

	token, c = parser.Read()
	fmt.Printf("Read: %s %c\n", token, c)

	// Position 99 greater than current index, this will reset index to 0.
	c = parser.UnreadN(99)
	fmt.Printf("UnreadN(99): %c\n", c)

	token, c = parser.Read()
	fmt.Printf("Read: %s %c\n", token, c)

}

Output:

UnreadN(2): /
Read:  /
UnreadN(99): a
Read: a ,

Source Files

bytes.go parser.go

Version
v0.60.0 (latest)
Published
Feb 1, 2025
Platform
linux/amd64
Imports
4 packages
Last checked
10 minutes ago –

Tools for package owners.