mirrors/madlisp
1
0
Fork 0
mirror of https://github.com/peklaiho/madlisp.git synced 2024-11-22 21:35:03 +00:00
Code Issues Packages Projects Releases Wiki Activity

add if

Browse Source
This commit is contained in:
Pekka Laiho 2020-05-30 19:02:41 +07:00
parent 01e5c4b198
commit a4182f7d8e
1 changed files with 14 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
src/Evaller.php
View File

@ -60,6 +60,20 @@ class Evaller
$value = $this->doEval($ast->get(2), $env); $value = $this->doEval($ast->get(2), $env);
return $env->set($ast->get(1)->getName(), $value); return $env->set($ast->get(1)->getName(), $value);
} elseif ($ast->get(0)->getName() == 'if') {
if ($ast->count() < 3 || $ast->count() > 4) {
throw new MadLispException("if requires 2 or 3 arguments");
}
$result = $this->doEval($ast->get(1), $env);
if ($result == true) {
return $this->doEval($ast->get(2), $env);
} elseif ($ast->count() == 4) {
return $this->doEval($ast->get(3), $env);
} else {
return null;
}
} elseif ($ast->get(0)->getName() == 'let') { } elseif ($ast->get(0)->getName() == 'let') {
if ($ast->count() != 3) { if ($ast->count() != 3) {
throw new MadLispException("let requires exactly 2 arguments"); throw new MadLispException("let requires exactly 2 arguments");