94a3a60e49
+ allow passing a scope to MondoRunner.run + make def a side effect + proper lambda with multiple args + closure
36 lines
1.1 KiB
Markdown
36 lines
1.1 KiB
Markdown
# mondo
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an experimental parser for an *uzulang*, a custom dsl for patterns that can stand on its own feet. more info:
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- [uzulang I](https://garten.salat.dev/uzu/uzulang1.html)
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- [uzulang II](https://garten.salat.dev/uzu/uzulang2.html)
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## Example Usage
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```js
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import { MondoRunner } from 'mondo'
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// define our library of functions and variables
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let lib = {
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add: (a, b) => a + b,
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mul: (a, b) => a * b,
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PI: Math.PI,
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};
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// this function will evaluate nodes in the syntax tree
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function evaluator(node) {
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// check if node is a leaf node (!= list)
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if (node.type !== 'list') {
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// check lib if we find a match in the lib, otherwise return value
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return lib[node.value] ?? node.value;
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}
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// now it can only be a list..
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const [fn, ...args] = node.children;
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// children in a list will already be evaluated
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// the first child is expected to be a function
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if (typeof fn !== 'function') {
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throw new Error(`"${fn}" is not a function`);
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}
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return fn(...args);
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}
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const runner = new MondoRunner({ evaluator });
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const pat = runner.run('add 1 (mul 2 PI)') // 7.283185307179586
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```
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