finished testing #30
finished testing #30
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testing_exercise/testing.js
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| function replaceWith(str, target, replacement){ | ||
| return str | ||
| .split('') | ||
| .map(function(v,i,a){ |
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small thing, but if you're not using the other arguments i and a, you don't need to include them in the callback. your callback can just be a function of a single parameter.
testing_exercise/testing.js
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| function mergeObjects(...args) { | ||
| return args.reduce(function(t,v,i,a){ | ||
| Object.keys(v).forEach(function(sv, si, sa){ |
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same comment as above - your callbacks here only need to reference the variables you're actually using.
testing_exercise/testing.js
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| } | ||
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| function mergeArrays(arr1, arr2) { | ||
| return arr1.concat(arr2).sort(); |
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one gotcha to be aware of with sort - it won't sort numbers correctly! The default sort in JavaScript is alphabetical, so for example:
[23,1,4].sort() // [1, 23, 4]
The example doesn't catch this.
To fix this, you can pass in a comparator to the sort function telling it how it should sort. reference
ajax_with_jquery_exercise/index.js
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| return Promise.all(topstories.slice(0,50).map(function(v,i){ | ||
| return $.get( | ||
| `https://hacker-news.firebaseio.com/v0/' | ||
| + 'item/${topstories[i]}.json?print=pretty`) |
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It looks like you mixed single quotes and back tics. I'm not sure what that does actually.
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I think you want to use two string templates:
`https://hacker-news.firebase.io.com/v0/`
+ `item/${topstories[i]}.json?print=pretty`
| this.favoriteColor = favoriteColor; | ||
| this.favoriteNumber = favoriteNumber; | ||
| this.favoriteFoods = favoriteFoods; | ||
| this.fullName = function(){ return `${this.firstName} ${this.lastName}`;}; |
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Add this to the prototype instead of the object. That way you reduce your memory usage.
| return this.family.length; | ||
| }; | ||
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| Array.prototype.map = function(fn, keepUndefined = false){ |
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the second parameter to push is used to set the keyword this in the callback function. So it would be something like:
newArr.push(fn.call(thisArg, this[i], i, this));
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| Array.prototype.reduce = function(fn, init, keepUndefined = false){ |
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I don't think reduce has a 3rd parameter.
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The original did not have 3 parameters. I had a use case that where I needed to fill in 'undefined' so I thought I would add it as a choice. Same with map. Because I gave it a default value it should not brake legacy code.
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