26 lines
506 B
Go
26 lines
506 B
Go
package main
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// Simple lexem stack implementation.
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import "github.com/neonxp/unilex"
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type lexemStack []unilex.Lexem
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func (ls *lexemStack) Head() (l unilex.Lexem) {
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if len(*ls) == 0 {
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return unilex.Lexem{Type: unilex.LexEOF}
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}
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return (*ls)[len(*ls)-1]
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}
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func (ls *lexemStack) Push(l unilex.Lexem) {
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*ls = append(*ls, l)
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}
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func (ls *lexemStack) Pop() (l unilex.Lexem) {
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if len(*ls) == 0 {
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return unilex.Lexem{Type: unilex.LexEOF}
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}
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*ls, l = (*ls)[:len(*ls)-1], (*ls)[len(*ls)-1]
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return l
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}
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