32 lines
498 B
Go
32 lines
498 B
Go
// Package lexer provides basic helpers to implement parsers
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package lexer
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import (
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"errors"
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"io"
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)
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// StateFn is a State Function of the parser
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type StateFn func() (StateFn, error)
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// Run runs a state machine until the state function either
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// returns nil or an error
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func Run(fn StateFn) error {
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for fn != nil {
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var err error
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fn, err = fn()
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switch {
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case errors.Is(err, io.EOF):
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// EOF
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return nil
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case err != nil:
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// failed
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return err
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}
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}
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// ended
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return nil
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}
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