function step5_tco(varargin), main(varargin), end % read function ret = READ(str) ret = reader.read_str(str); end % eval function ret = eval_ast(ast, env) switch class(ast) case 'types.Symbol' ret = env.get(ast); case 'types.List' ret = types.List(); for i=1:length(ast) ret.append(EVAL(ast.get(i), env)); end case 'types.Vector' ret = types.Vector(); for i=1:length(ast) ret.append(EVAL(ast.get(i), env)); end case 'types.HashMap' ret = types.HashMap(); ks = ast.keys(); for i=1:length(ks) k = ks{i}; ret.set(EVAL(k, env), EVAL(ast.get(k), env)); end otherwise ret = ast; end end function ret = EVAL(ast, env) while true %fprintf('EVAL: %s\n', printer.pr_str(ast, true)); if ~type_utils.list_Q(ast) ret = eval_ast(ast, env); return; end % apply if length(ast) == 0 ret = ast; return; end if isa(ast.get(1),'types.Symbol') a1sym = ast.get(1).name; else a1sym = '_@$fn$@_'; end switch (a1sym) case 'def!' ret = env.set(ast.get(2), EVAL(ast.get(3), env)); return; case 'let*' let_env = Env({env}); for i=1:2:length(ast.get(2)) let_env.set(ast.get(2).get(i), EVAL(ast.get(2).get(i+1), let_env)); end env = let_env; ast = ast.get(3); % TCO case 'do' el = eval_ast(ast.slice(2,length(ast)-1), env); ast = ast.get(length(ast)); % TCO case 'if' cond = EVAL(ast.get(2), env); if strcmp(class(cond), 'types.Nil') || ... (islogical(cond) && cond == false) if length(ast) > 3 ast = ast.get(4); % TCO else ret = type_utils.nil; return; end else ast = ast.get(3); % TCO end case 'fn*' fn = @(varargin) EVAL(ast.get(3), Env({env}, ast.get(2), ... types.List(varargin{:}))); ret = types.Function(fn, ast.get(3), env, ast.get(2)); return; otherwise el = eval_ast(ast, env); f = el.get(1); args = el.slice(2); if isa(f, 'types.Function') env = Env({f.env}, f.params, args); ast = f.ast; % TCO else ret = f(args.data{:}); return end end end end % print function ret = PRINT(ast) ret = printer.pr_str(ast, true); end % REPL function ret = rep(str, env) ret = PRINT(EVAL(READ(str), env)); end function main(args) repl_env = Env(); % core.m: defined using matlab ns = core.ns(); ks = ns.keys(); for i=1:length(ks) k = ks{i}; repl_env.set(types.Symbol(k), ns(k)); end % core.mal: defined using the langauge itself rep('(def! not (fn* (a) (if a false true)))', repl_env); %cleanObj = onCleanup(@() disp('*** here1 ***')); while (true) try line = input('user> ', 's'); catch err return end if strcmp(strtrim(line),''), continue, end try fprintf('%s\n', rep(line, repl_env)); catch err fprintf('Error: %s\n', err.message); type_utils.print_stack(err); end end end