*Abbreviations*: In an earlier version, you couldn't use abbreviations. `\x y. y x x` had to be written `(\x (\y ((y x) x)))`. We've upgraded the parser though, so now it should be able to understand any lambda term that you can.
-*Constants*: (NOT YET IMPLEMENTED!) The combinators `S`, `K`, `I`, `C`, `B`, `W`, and `T` are pre-defined to their standard values. Also, integers will automatically be converted to Church numerals. (`0` is `\s z. z`, `1` is `\s z. s z`, and so on.)
+*Constants*: The combinators `S`, `K`, `I`, `C`, `B`, `W`, and `T` are pre-defined to their standard values. Also, integers will automatically be converted to Church numerals. (`0` is `\s z. z`, `1` is `\s z. s z`, and so on.)
)
</textarea>
<input id="PARSE" value="Normalize" type="button">
+<input id="ETA" type="checkbox">do eta-reductions too
<noscript><p>You may not see it because you have JavaScript turned off. Uffff!</p></noscript>
<script src="/code/lambda.js"></script>
<script src="/code/tokens.js"></script>
var parse = make_parse();
function go(source) {
- var string, tree, expr;
+ var string, tree, expr, eta;
try {
tree = parse(source);
// string = JSON.stringify(tree, ['key', 'name', 'message', 'value', 'arity', 'first', 'second', 'third', 'fourth'], 4);
- string = JSON.stringify(tree.handler(), ['key', 'name', 'message', 'value', 'arity', 'first', 'second', 'tag', 'variable', 'left', 'right', 'bound', 'body' ], 4);
expr = tree.handler();
- // string = expr.to_string() + "\n\n~~>\n\n";
- // string = '';
- // string = string + reduce(expr, false, false).to_string();
+ // string = JSON.stringify(expr, ['key', 'name', 'message', 'value', 'arity', 'first', 'second', 'tag', 'variable', 'left', 'right', 'bound', 'body' ], 4);
+// string = expr.to_string() + "\n\n~~>\n\n";
+ string = '';
+ eta = document.getElementById('ETA').checked;
+ string = string + reduce(expr, eta, false).to_string();
} catch (e) {
string = JSON.stringify(e, ['name', 'message', 'from', 'to', 'key',
'value', 'arity', 'first', 'second', 'third', 'fourth'], 4);