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Try to work with Javascript's arrays, it's a nightmare. Fun fact: let list = new Array(5); list.forEach(() => { console.log("foo"); }) Will display nothi

Try to work with Javascript's arrays, it's a nightmare. Fun fact: let list = new Array(5); list.forEach(() => { console.log("foo"); }) Will display nothing, if you want to properly initialize an array with a defined length, you have to do: let list = Array.apply(null, Array(5)).map(function () {}) I make web games in Typescript, and I get all sorts of problems like this everytime I have to work with 2D arrays, problems that I don't get when I do games in C# with Unity. Unity's modified Javascript actually implements better arrays and recommends not using Javascript's native arrays: http://docs.unity3d.com/ScriptReference/Array.html http://docs.unity3d.com/ScriptReference/Array.html

WorldMaker 10y ago
You seem to be trying to fit a square peg into a star-shaped hole. Arrays in JS are actually misnamed, they are actually Lists. For game scripting you may want to make heavy use of Typed Arrays [1], which are more like the arrays you seem to be looking for. [1] https://developer.mozilla.org/en-US/docs/Web/JavaScript/Typed_arrays https://developer.mozilla.org/en-US/docs/Web/JavaScript/Type...
oceanswave 10y ago
so use the more common for(let v of list) { console.log("foo"); } If you're saying that "initialize an array with a defined length" should be "initialize an empty array of 5 values of undefined" then yeah, but you can also use: let list = Array.from(Array(5)); as new Array(5) creates an array of length 5, but each is a "hole" I know the syntax is similar to C# or other languages, but because it's slightly different doesn't mean it doesn't bring anything to the table. JS or TS != C# in a browser the syntax is similar...
krisdol 10y ago
for loops will yield better performance and the result you want to get. If you're trying to log 5 times you shouldn't be wasting memory with allocating an array or needlessly calling the forEach function or needlessly creating a callback. You're just wasting garbage collection and cpu time with this

WorldMaker 10y ago

You seem to be trying to fit a square peg into a star-shaped hole. Arrays in JS are actually misnamed, they are actually Lists. For game scripting you may want to make heavy use of Typed Arrays [1], which are more like the arrays you seem to be looking for. [1] https://developer.mozilla.org/en-US/docs/Web/JavaScript/Typed_arrays https://developer.mozilla.org/en-US/docs/Web/JavaScript/Type...

oceanswave 10y ago

so use the more common for(let v of list) { console.log("foo"); } If you're saying that "initialize an array with a defined length" should be "initialize an empty array of 5 values of undefined" then yeah, but you can also use: let list = Array.from(Array(5)); as new Array(5) creates an array of length 5, but each is a "hole" I know the syntax is similar to C# or other languages, but because it's slightly different doesn't mean it doesn't bring anything to the table. JS or TS != C# in a browser the syntax is similar...

krisdol 10y ago

for loops will yield better performance and the result you want to get. If you're trying to log 5 times you shouldn't be wasting memory with allocating an array or needlessly calling the forEach function or needlessly creating a callback. You're just wasting garbage collection and cpu time with this