#!/usr/bin/env bash

source $[dirname $0]/reader.sh
source $[dirname $0]/printer.sh

# read
proc READ {
    test $(1) && setglobal r = $(1) || READLINE
    READ_STR $(r)
}

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

# print
proc PRINT {
    if [[ "${__ERROR}" ]] {
        _pr_str $(__ERROR) yes
        setglobal r = ""Error: $(r)""
        setglobal __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)
}