39 lines
1.1 KiB
Go
39 lines
1.1 KiB
Go
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package cursor
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import "io"
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// BufferedReaderAt uses a buffer to supplement an io.Reader
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// with limited backward seeking.
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type BufferedReaderAt struct{}
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func NewBufferedReaderAt(r io.Reader, minBuffer uint64) *BufferedReaderAt
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// ReadAt reads bytes from the underlying reader. If the offset is after
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// the end of the buffer, ReadAt will first read and ignore bytes from the
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// underlying reader until it reaches the offset. If the offset is
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// before the start of the buffer, ReadAt will return an error.
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//
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// If your parser needs unlimited lookahead, you should probably
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// just read the whole input into a slice and use BytesCursor.
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func (b *BufferedReaderAt) ReadAt(dst []byte, offset int64) (int, error)
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// RuneReader is an io.RuneReader backed by a Cursor, for compatibility
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// with the regexp package.
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type RuneReader struct {
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cursor Cursor[byte]
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}
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func NewRuneReader(c Cursor[byte]) *RuneReader {
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return &RuneReader{cursor: c}
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}
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func (r *RuneReader) Read(dst []byte) (int, error) {
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n, c, err := r.cursor.Read(dst)
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r.cursor = c
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return int(n), err
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}
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func (r *RuneReader) Cursor() Cursor[byte] {
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return r.cursor
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}
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