#!/usr/bin/env bash source $(dirname $0)/reader.sh source $(dirname $0)/printer.sh source $(dirname $0)/env.sh source $(dirname $0)/core.sh # read READ () { [ "${1}" ] && r="${1}" || READLINE READ_STR "${r}" } # eval EVAL_AST () { local ast="${1}" env="${2}" #_pr_str "${ast}"; echo "EVAL_AST '${ast}:${r} / ${env}'" _obj_type "${ast}"; local ot="${r}" case "${ot}" in symbol) ENV_GET "${env}" "${ast}" return ;; list) _map_with_type _list EVAL "${ast}" "${env}" ;; vector) _map_with_type _vector EVAL "${ast}" "${env}" ;; hash_map) local res="" key= val="" hm="${ANON["${ast}"]}" _hash_map; local new_hm="${r}" eval local keys="\${!${hm}[@]}" for key in ${keys}; do eval val="\${${hm}[\"${key}\"]}" EVAL "${val}" "${env}" _assoc! "${new_hm}" "${key}" "${r}" done r="${new_hm}" ;; *) r="${ast}" ;; esac } EVAL () { local ast="${1}" env="${2}" r= [[ "${__ERROR}" ]] && return 1 #_pr_str "${ast}"; echo "EVAL '${r} / ${env}'" _obj_type "${ast}"; local ot="${r}" if [[ "${ot}" != "list" ]]; then EVAL_AST "${ast}" "${env}" return fi _empty? "${ast}" && r="${ast}" && return # apply list _nth "${ast}" 0; local a0="${r}" _nth "${ast}" 1; local a1="${r}" _nth "${ast}" 2; local a2="${r}" case "${ANON["${a0}"]}" in def!) EVAL "${a2}" "${env}" [[ "${__ERROR}" ]] && return 1 ENV_SET "${env}" "${a1}" "${r}" return ;; let*) ENV "${env}"; local let_env="${r}" local let_pairs=(${ANON["${a1}"]}) local idx=0 #echo "let: [${let_pairs[*]}] for ${a2}" while [[ "${let_pairs["${idx}"]}" ]]; do EVAL "${let_pairs[$(( idx + 1))]}" "${let_env}" ENV_SET "${let_env}" "${let_pairs[${idx}]}" "${r}" idx=$(( idx + 2)) done EVAL "${a2}" "${let_env}" return ;; do) _rest "${ast}" EVAL_AST "${r}" "${env}" [[ "${__ERROR}" ]] && r= && return 1 _last "${r}" return ;; if) EVAL "${a1}" "${env}" [[ "${__ERROR}" ]] && return 1 if [[ "${r}" == "${__false}" || "${r}" == "${__nil}" ]]; then # eval false form _nth "${ast}" 3; local a3="${r}" if [[ "${a3}" ]]; then EVAL "${a3}" "${env}" else r="${__nil}" fi else # eval true condition EVAL "${a2}" "${env}" fi return ;; fn*) _function "ENV \"${env}\" \"${a1}\" \"\${@}\"; \ EVAL \"${a2}\" \"\${r}\"" return ;; *) EVAL_AST "${ast}" "${env}" [[ "${__ERROR}" ]] && r= && return 1 local el="${r}" _first "${el}"; local f="${ANON["${r}"]}" _rest "${el}"; local args="${ANON["${r}"]}" #echo "invoke: ${f} ${args}" eval ${f} ${args} return ;; esac } # print PRINT () { if [[ "${__ERROR}" ]]; then _pr_str "${__ERROR}" yes r="Error: ${r}" __ERROR= else _pr_str "${1}" yes fi } # repl ENV; REPL_ENV="${r}" REP () { r= READ "${1}" EVAL "${r}" "${REPL_ENV}" PRINT "${r}" } # core.sh: defined using bash _fref () { _symbol "${1}"; local sym="${r}" _function "${2} \"\${@}\"" ENV_SET "${REPL_ENV}" "${sym}" "${r}" } for n in "${!core_ns[@]}"; do _fref "${n}" "${core_ns["${n}"]}"; done # core.mal: defined using the language itself REP "(def! not (fn* (a) (if a false true)))" # repl loop while true; do READLINE "user> " || exit "$?" [[ "${r}" ]] && REP "${r}" && echo "${r}" done