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function step2_eval(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(ast.name);
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)
%fprintf('EVAL: %s\n', printer.pr_str(ast, true));
if ~types.list_Q(ast)
ret = eval_ast(ast, env);
return;
end
% apply
el = eval_ast(ast, env);
f = el.get(1);
args = el.data(2:end);
ret = f(args{:});
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 = containers.Map();
repl_env('+') = @(a,b) a+b;
repl_env('-') = @(a,b) a-b;
repl_env('*') = @(a,b) a*b;
repl_env('/') = @(a,b) floor(a/b);
%cleanObj = onCleanup(@() disp('*** here1 ***'));
while (true)
line = input('user> ', 's');
if strcmp(strtrim(line),''), continue, end
try
fprintf('%s\n', rep(line, repl_env));
catch err
fprintf('Error: %s\n', err.message);
fprintf('%s\n', getReport(err, 'extended'));
end
end
end
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