go/src/step0_repl/step0_repl.go


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package main

import (
    "bufio"
    "fmt"
    "os"
    "strings"
)

// 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() {
    reader := bufio.NewReader(os.Stdin);
    // repl loop
    for {
        fmt.Print("user> ");
        text, err := reader.ReadString('\n');
        text = strings.TrimRight(text, "\n");
        if (err != nil) {
            return
        }
        fmt.Println(rep(text))
    }
}