go/src/step0_repl/step0_repl.go


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package main

import (
	"fmt"
	"strings"
)

import (
	"readline"
)

// read
func READ(str string) string {
	return str
}

// eval
func EVAL(ast string, env string) string {
	return ast
}

// print
func PRINT(exp string) string {
	return exp
}

// repl
func rep(str string) string {
	return PRINT(EVAL(READ(str), ""))
}

func main() {
	// repl loop
	for {
		text, err := readline.Readline("user> ")
		text = strings.TrimRight(text, "\n")
		if err != nil {
			return
		}
		fmt.Println(rep(text))
	}
}