#!/usr/bin/env bash

source $(dirname $0)/reader.sh
source $(dirname $0)/printer.sh

# read
proc READ {
    test ${1} && setvar r = "${1}" || READLINE
    READ_STR ${r}
}

# eval
proc EVAL {
    local ast="${1}"
    local env="${2}"
    setvar r = ''
    [[ "${__ERROR}" ]] && return 1
    setvar r = "${ast}"
}

# print
proc PRINT {
    if [[ "${__ERROR}" ]] {
        _pr_str ${__ERROR} yes
        setvar r = ""Error: ${r}""
        setvar __ERROR = ''
    } else {
        _pr_str ${1} yes
    }
}

# repl
proc REP {
    READ ${1}
    EVAL ${r}
    PRINT ${r}
}

# repl loop
while true {
    READLINE "user> " || exit "$?"
    [[ "${r}" ]] && REP ${r} && echo ${r}
}