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mirror of https://github.com/kanaka/mal.git synced 2024-11-10 12:47:45 +03:00
mal/plpgsql/step8_macros.sql
Joel Martin 494792abe4 plpgsql: schema namespaces. refactor IO.
- move each file to a schema namespace. Don't recreate DB, just the
  schemas. This is much faster and avoids the error about user still
  using the DB when recreating the DB.
- combine RUN and MAIN_LOOP into MAIN routine.
- add open column to streams table
- close stream 1 in MAIN
2016-05-02 23:37:16 -05:00

337 lines
10 KiB
PL/PgSQL

-- ---------------------------------------------------------
-- step8_macros.sql
\i init.sql
\i io.sql
\i types.sql
\i reader.sql
\i printer.sql
\i envs.sql
\i core.sql
-- ---------------------------------------------------------
CREATE SCHEMA mal;
-- read
CREATE FUNCTION mal.READ(line varchar) RETURNS integer AS $$
BEGIN
RETURN reader.read_str(line);
END; $$ LANGUAGE plpgsql;
-- eval
CREATE FUNCTION mal.is_pair(ast integer) RETURNS boolean AS $$
BEGIN
RETURN types._sequential_Q(ast) AND types._count(ast) > 0;
END; $$ LANGUAGE plpgsql;
CREATE FUNCTION mal.quasiquote(ast integer) RETURNS integer AS $$
DECLARE
a0 integer;
a00 integer;
BEGIN
IF NOT mal.is_pair(ast) THEN
RETURN types._list(ARRAY[types._symbolv('quote'), ast]);
ELSE
a0 := types._nth(ast, 0);
IF types._symbol_Q(a0) AND a0 = types._symbolv('unquote') THEN
RETURN types._nth(ast, 1);
ELSE
a00 := types._nth(a0, 0);
IF types._symbol_Q(a00) AND
a00 = types._symbolv('splice-unquote') THEN
RETURN types._list(ARRAY[types._symbolv('concat'),
types._nth(a0, 1),
mal.quasiquote(types._rest(ast))]);
END IF;
END IF;
RETURN types._list(ARRAY[types._symbolv('cons'),
mal.quasiquote(types._first(ast)),
mal.quasiquote(types._rest(ast))]);
END IF;
END; $$ LANGUAGE plpgsql;
CREATE FUNCTION mal.is_macro_call(ast integer, env integer) RETURNS boolean AS $$
DECLARE
a0 integer;
f integer;
result boolean = false;
BEGIN
IF types._list_Q(ast) THEN
a0 = types._first(ast);
IF types._symbol_Q(a0) AND
envs.find(env, types._valueToString(a0)) IS NOT NULL THEN
f := envs.get(env, a0);
SELECT macro INTO result FROM types.value WHERE value_id = f;
END IF;
END IF;
RETURN result;
END; $$ LANGUAGE plpgsql;
CREATE FUNCTION mal.macroexpand(ast integer, env integer) RETURNS integer AS $$
DECLARE
mac integer;
BEGIN
WHILE mal.is_macro_call(ast, env)
LOOP
mac := envs.get(env, types._first(ast));
ast := types._apply(mac, types._valueToArray(types._rest(ast)));
END LOOP;
RETURN ast;
END; $$ LANGUAGE plpgsql;
CREATE FUNCTION mal.eval_ast(ast integer, env integer) RETURNS integer AS $$
DECLARE
type integer;
seq integer[];
eseq integer[];
hash hstore;
ehash hstore;
kv RECORD;
e integer;
result integer;
BEGIN
SELECT type_id INTO type FROM types.value WHERE value_id = ast;
CASE
WHEN type = 7 THEN
BEGIN
result := envs.get(env, ast);
END;
WHEN type IN (8, 9) THEN
BEGIN
SELECT val_seq INTO seq FROM types.value WHERE value_id = ast;
-- Evaluate each entry creating a new sequence
FOR i IN 1 .. COALESCE(array_length(seq, 1), 0) LOOP
eseq[i] := mal.EVAL(seq[i], env);
END LOOP;
INSERT INTO types.value (type_id, val_seq) VALUES (type, eseq)
RETURNING value_id INTO result;
END;
WHEN type = 10 THEN
BEGIN
SELECT val_hash INTO hash FROM types.value WHERE value_id = ast;
-- Evaluate each value for every key/value
FOR kv IN SELECT * FROM each(hash) LOOP
e := mal.EVAL(CAST(kv.value AS integer), env);
IF ehash IS NULL THEN
ehash := hstore(kv.key, CAST(e AS varchar));
ELSE
ehash := ehash || hstore(kv.key, CAST(e AS varchar));
END IF;
END LOOP;
INSERT INTO types.value (type_id, val_hash) VALUES (type, ehash)
RETURNING value_id INTO result;
END;
ELSE
result := ast;
END CASE;
RETURN result;
END; $$ LANGUAGE plpgsql;
CREATE FUNCTION mal.EVAL(ast integer, env integer) RETURNS integer AS $$
DECLARE
type integer;
a0 integer;
a0sym varchar;
a1 integer;
let_env integer;
idx integer;
binds integer[];
el integer;
fn integer;
fname varchar;
args integer[];
cond integer;
fast integer;
fparams integer;
fenv integer;
result integer;
BEGIN
LOOP
-- PERFORM writeline(format('EVAL: %s [%s]', pr_str(ast), ast));
SELECT type_id INTO type FROM types.value WHERE value_id = ast;
IF type <> 8 THEN
RETURN mal.eval_ast(ast, env);
END IF;
ast := mal.macroexpand(ast, env);
SELECT type_id INTO type FROM types.value WHERE value_id = ast;
IF type <> 8 THEN
RETURN mal.eval_ast(ast, env);
END IF;
IF types._count(ast) = 0 THEN
RETURN ast;
END IF;
a0 := types._first(ast);
IF types._symbol_Q(a0) THEN
a0sym := (SELECT val_string FROM types.value WHERE value_id = a0);
ELSE
a0sym := '__<*fn*>__';
END IF;
CASE
WHEN a0sym = 'def!' THEN
BEGIN
RETURN envs.set(env, types._nth(ast, 1),
mal.EVAL(types._nth(ast, 2), env));
END;
WHEN a0sym = 'let*' THEN
BEGIN
let_env := envs.new(env);
a1 := types._nth(ast, 1);
binds := (SELECT val_seq FROM types.value WHERE value_id = a1);
idx := 1;
WHILE idx < array_length(binds, 1) LOOP
PERFORM envs.set(let_env, binds[idx],
mal.EVAL(binds[idx+1], let_env));
idx := idx + 2;
END LOOP;
env := let_env;
ast := types._nth(ast, 2);
CONTINUE; -- TCO
END;
WHEN a0sym = 'quote' THEN
BEGIN
RETURN types._nth(ast, 1);
END;
WHEN a0sym = 'quasiquote' THEN
BEGIN
ast := mal.quasiquote(types._nth(ast, 1));
CONTINUE; -- TCO
END;
WHEN a0sym = 'defmacro!' THEN
BEGIN
fn := mal.EVAL(types._nth(ast, 2), env);
fn := types._macro(fn);
RETURN envs.set(env, types._nth(ast, 1), fn);
END;
WHEN a0sym = 'macroexpand' THEN
BEGIN
RETURN mal.macroexpand(types._nth(ast, 1), env);
END;
WHEN a0sym = 'do' THEN
BEGIN
PERFORM mal.eval_ast(types._slice(ast, 1, types._count(ast)-1), env);
ast := types._nth(ast, types._count(ast)-1);
CONTINUE; -- TCO
END;
WHEN a0sym = 'if' THEN
BEGIN
cond := mal.EVAL(types._nth(ast, 1), env);
SELECT type_id INTO type FROM types.value WHERE value_id = cond;
IF type = 0 OR type = 1 THEN -- nil or false
IF types._count(ast) > 3 THEN
ast := types._nth(ast, 3);
CONTINUE; -- TCO
ELSE
RETURN 0; -- nil
END IF;
ELSE
ast := types._nth(ast, 2);
CONTINUE; -- TCO
END IF;
END;
WHEN a0sym = 'fn*' THEN
BEGIN
RETURN types._malfunc(types._nth(ast, 2), types._nth(ast, 1), env);
END;
ELSE
BEGIN
el := mal.eval_ast(ast, env);
SELECT type_id, val_string, ast_id, params_id, env_id
INTO type, fname, fast, fparams, fenv
FROM types.value WHERE value_id = types._first(el);
args := types._restArray(el);
IF type = 11 THEN
EXECUTE format('SELECT %s($1);', fname)
INTO result USING args;
RETURN result;
ELSIF type = 12 THEN
env := envs.new(fenv, fparams, args);
ast := fast;
CONTINUE; -- TCO
ELSE
RAISE EXCEPTION 'Invalid function call';
END IF;
END;
END CASE;
END LOOP;
END; $$ LANGUAGE plpgsql;
-- print
CREATE FUNCTION mal.PRINT(exp integer) RETURNS varchar AS $$
BEGIN
RETURN printer.pr_str(exp);
END; $$ LANGUAGE plpgsql;
-- repl
-- repl_env is environment 0
CREATE FUNCTION mal.REP(line varchar) RETURNS varchar AS $$
BEGIN
RETURN mal.PRINT(mal.EVAL(mal.READ(line), 0));
END; $$ LANGUAGE plpgsql;
-- core.sql: defined using SQL (in core.sql)
-- repl_env is created and populated with core functions in by core.sql
CREATE FUNCTION mal.mal_eval(args integer[]) RETURNS integer AS $$
BEGIN
RETURN mal.EVAL(args[1], 0);
END; $$ LANGUAGE plpgsql;
INSERT INTO types.value (type_id, val_string) VALUES (11, 'mal.mal_eval');
SELECT envs.vset(0, 'eval',
(SELECT value_id FROM types.value
WHERE val_string = 'mal.mal_eval')) \g '/dev/null'
-- *ARGV* values are set by RUN
SELECT envs.vset(0, '*ARGV*', mal.READ('()')) \g '/dev/null'
-- core.mal: defined using the language itself
SELECT mal.REP('(def! not (fn* (a) (if a false true)))') \g '/dev/null'
SELECT mal.REP('(def! load-file (fn* (f) (eval (read-string (str "(do " (slurp f) ")")))))') \g '/dev/null'
SELECT mal.REP('(defmacro! cond (fn* (& xs) (if (> (count xs) 0) (list ''if (first xs) (if (> (count xs) 1) (nth xs 1) (throw "odd number of forms to cond")) (cons ''cond (rest (rest xs)))))))') \g '/dev/null'
SELECT mal.REP('(defmacro! or (fn* (& xs) (if (empty? xs) nil (if (= 1 (count xs)) (first xs) `(let* (or_FIXME ~(first xs)) (if or_FIXME or_FIXME (or ~@(rest xs))))))))') \g '/dev/null'
CREATE FUNCTION mal.MAIN(pwd varchar, argstring varchar DEFAULT NULL)
RETURNS integer AS $$
DECLARE
line varchar;
output varchar;
allargs integer;
BEGIN
PERFORM envs.vset(0, '*PWD*', types._stringv(pwd));
IF argstring IS NOT NULL THEN
allargs := mal.READ(argstring);
PERFORM envs.vset(0, '*ARGV*', types._rest(allargs));
PERFORM mal.REP('(load-file ' ||
printer.pr_str(types._first(allargs)) || ')');
PERFORM io.close(1);
PERFORM io.wait_flushed(1);
RETURN 0;
END IF;
WHILE true
LOOP
BEGIN
line := io.readline('user> ', 0);
IF line IS NULL THEN
PERFORM io.close(1);
RETURN 0;
END IF;
IF line NOT IN ('', E'\n') THEN
output := mal.REP(line);
PERFORM io.writeline(output);
END IF;
EXCEPTION WHEN OTHERS THEN
PERFORM io.writeline('Error: ' || SQLERRM);
END;
END LOOP;
END; $$ LANGUAGE plpgsql;