53 lines
782 B
Go
53 lines
782 B
Go
// Buffer is responsible for reading bytes from input, decode runes
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// and stream those to the lexer
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package buffer
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import (
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"bufio"
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"bytes"
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"io"
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)
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type (
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Buffer struct {
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input *bufio.Reader
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ready chan rune
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}
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)
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func NewBytesBuffer(b []byte) *Buffer {
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return NewReaderBuffer(bytes.NewReader(b))
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}
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func NewReaderBuffer(rd io.Reader) *Buffer {
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return New(bufio.NewReader(rd))
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}
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func New(input *bufio.Reader) *Buffer {
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b := &Buffer{
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input: input,
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ready: make(chan rune, 100),
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}
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go b.stream()
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return b
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}
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func (b *Buffer) Next() rune {
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if next, ok := <-b.ready; ok {
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return next
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} else {
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return 0
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}
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}
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func (b *Buffer) stream() {
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defer close(b.ready)
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for {
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if r, _, err := b.input.ReadRune(); err == nil {
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b.ready <- r
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} else {
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return
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}
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}
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}
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