70 lines
1.1 KiB
Go
70 lines
1.1 KiB
Go
package strftime
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type parser struct {
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fmt string
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specs map[byte]string
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unpadded map[byte]string
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writeLit func(byte) error
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writeFmt func(string) error
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fallback func(spec byte, pad bool) error
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}
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func (p *parser) parse() error {
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const (
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initial = iota
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specifier
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nopadding
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)
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var err error
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state := initial
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for _, b := range []byte(p.fmt) {
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switch state {
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default:
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if b == '%' {
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state = specifier
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} else {
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err = p.writeLit(b)
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}
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case specifier:
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if b == '-' {
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state = nopadding
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continue
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}
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if fmt, ok := p.specs[b]; ok {
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err = p.writeFmt(fmt)
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} else {
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err = p.fallback(b, true)
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}
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state = initial
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case nopadding:
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if fmt, ok := p.unpadded[b]; ok {
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err = p.writeFmt(fmt)
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} else if fmt, ok := p.specs[b]; ok {
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err = p.writeFmt(fmt)
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} else {
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err = p.fallback(b, false)
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}
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state = initial
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}
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if err != nil {
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return err
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}
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}
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switch state {
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default:
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return nil
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case specifier:
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return p.writeLit('%')
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case nopadding:
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err := p.writeLit('%')
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if err != nil {
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return err
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}
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return p.writeLit('-')
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}
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}
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