36 lines
728 B
Go
36 lines
728 B
Go
package main
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import (
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"time"
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"github.com/alecthomas/participle/v2"
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"github.com/alecthomas/participle/v2/lexer"
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)
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var basicLexer = lexer.MustSimple([]lexer.SimpleRule{
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{"Identifier", `[a-zA-Z_][a-zA-Z0-9_]*`},
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{"Date", `\d{4}-\d{2}-\d{2}`},
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{"Timestamp", `\d{4}-\d{2}-\d{2}T?\d{2}:\d{2}:\d{2}Z?`},
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{"Time", `\d{2}:\d{2}:\d{2}Z?`},
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{"Int", `\d+`},
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{"Whitespace", `[ ]+`},
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})
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var parser = participle.MustBuild[Atom](
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participle.Lexer(basicLexer),
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participle.Elide("Whitespace"),
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)
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func Parse(expr string) (TimeResult, error) {
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res, err := parser.ParseString("expr", expr)
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if err != nil {
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return nil, err
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}
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return res, nil
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}
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type TimeResult interface {
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Time() (time.Time, error)
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RequiresRefreshing() bool
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}
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