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// nolint: golint, dupl
package main
import (
"os"
"github.com/alecthomas/kong"
"github.com/alecthomas/participle/v2"
"github.com/alecthomas/participle/v2/lexer"
)
var (
basicLexer = lexer.MustSimple([]lexer.SimpleRule{
{"Comment", `(?i)rem[^\n]*`},
{"String", `"(\\"|[^"])*"`},
{"Number", `[-+]?(\d*\.)?\d+`},
{"Ident", `[a-zA-Z_]\w*`},
{"Punct", `[-[!@#$%^&*()+_={}\|:;"'<,>.?/]|]`},
{"EOL", `[\n\r]+`},
{"whitespace", `[ \t]+`},
})
basicParser = participle.MustBuild[Program](
participle.Lexer(basicLexer),
participle.CaseInsensitive("Ident"),
participle.Unquote("String"),
participle.UseLookahead(2),
)
cli struct {
File string `arg:"" type:"existingfile" help:"File to parse."`
}
)
func main() {
ctx := kong.Parse(&cli)
r, err := os.Open(cli.File)
ctx.FatalIfErrorf(err)
defer r.Close()
program, err := Parse(r)
ctx.FatalIfErrorf(err)
funcs := map[string]Function{
"ADD": func(args ...interface{}) (interface{}, error) {
return args[0].(float64) + args[1].(float64), nil
},
}
err = program.Evaluate(os.Stdin, os.Stdout, funcs)
ctx.FatalIfErrorf(err)
}
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