807dd273fd
the reminder not showing content on the card at dashboard view and the quizes are hardcoded must move to the db make api's for it
64 lines
1.4 KiB
Markdown
64 lines
1.4 KiB
Markdown
# undefsafe
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Simple *function* for retrieving deep object properties without getting "Cannot read property 'X' of undefined"
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Can also be used to safely set deep values.
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## Usage
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```js
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var object = {
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a: {
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b: {
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c: 1,
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d: [1,2,3],
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e: 'remy'
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}
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}
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};
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console.log(undefsafe(object, 'a.b.e')); // "remy"
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console.log(undefsafe(object, 'a.b.not.found')); // undefined
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```
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Demo: [https://jsbin.com/eroqame/3/edit?js,console](https://jsbin.com/eroqame/3/edit?js,console)
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## Setting
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```js
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var object = {
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a: {
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b: [1,2,3]
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}
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};
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// modified object
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var res = undefsafe(object, 'a.b.0', 10);
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console.log(object); // { a: { b: [10, 2, 3] } }
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console.log(res); // 1 - previous value
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```
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## Star rules in paths
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As of 1.2.0, `undefsafe` supports a `*` in the path if you want to search all of the properties (or array elements) for a particular element.
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The function will only return a single result, either the 3rd argument validation value, or the first positive match. For example, the following github data:
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```js
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const githubData = {
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commits: [{
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modified: [
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"one",
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"two"
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]
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}, /* ... */ ]
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};
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// first modified file found in the first commit
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console.log(undefsafe(githubData, 'commits.*.modified.0'));
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// returns `two` or undefined if not found
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console.log(undefsafe(githubData, 'commits.*.modified.*', 'two'));
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```
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