Created
February 16, 2020 17:06
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Memoization decorator for javascript functions
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/* | |
function memoize(f) { | |
return function(...p){ | |
this._cache = this._cache || [] | |
var k = p.join('|') | |
return this._cache[k] || (this._cache[k] = f(...p)) | |
} | |
} | |
*/ | |
const memoize=(f)=>(...p)=>(this._=this._||[])[k=p.join('|')]||(this._[k]=f(...p)) | |
/** EXAMPLE **/ | |
function foo(index) { | |
// Return a non-determonistic value (for testing purposes) | |
return "" + index + ":" + (Math.random()*100000|0) | |
} | |
// Add memoization to foo function | |
foo = memoize(foo) | |
console.log( | |
foo(1), // RANDOM VALUE (A) | |
foo(1), // SAME as A | |
foo(2), // RANDOM VALUE (B) | |
foo(3), // RANDOM VALUE (C) | |
foo(1), // SAME as A | |
foo(1), // SAME as A | |
foo(3) // SAME as C | |
) |
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