Marek Piasecki
2 years ago
1 changed files with 70 additions and 0 deletions
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# I'm confused with class `get` `set` and `prop` |
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We have 2 places in documentation describing it: |
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[A] |
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[https://imba.io/docs/basic-syntax/classes#computed-properties](https://imba.io/docs/basic-syntax/classes#computed-properties) |
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[B] |
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[https://imba.io/docs/basic-syntax/operators#keywords-set](https://imba.io/docs/basic-syntax/operators#keywords-set) |
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__[A]__ describes: |
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`get` |
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> The get syntax binds an object property to a function that will be |
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> called when that property is looked up |
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But there's no bind. If you call `get` the same as property you get into |
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infinite loop. If you call it differently - like in examples on website |
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which doesn't support the description clame - |
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then it works like a regular function and no difference between using |
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`get` or `def` other than self documenting syntax. |
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__1. What's the differenece between `get` and `def`?__ |
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`set` |
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> Using set you can define a function that will be called when there is |
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> an attempt to set that property. |
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Sounds clear but then example doesn't show it and then it's not clear |
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until you check it. Proper example: |
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```coffee |
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class Rect |
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sides = 0 |
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width = 0 |
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height = 0 |
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set sides size |
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width = size |
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height = size |
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``` |
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I would expect different behaviour from `set` - method is called on |
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value change > process value > returns processed value > applies |
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returned value instead. Probably the thing which is proposed in |
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undocumented section as `$set` but with not practical syntax. |
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__2. I see no consistency between `get` and `set` as set binds on write |
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and get doesn't bind on lookup.__ |
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No `prop` description or usage in any example of Class documentation. |
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__[B]__ describes `prop` and use it in examples: |
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`prop` |
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>A prop allows a tag property to be set from the outside |
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But you have the same behaviour without keyword prop. |
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__3. What's the difference between following?__ |
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```coffee |
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class A |
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prop a = 1 |
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# and |
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class B |
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b = 1 |
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``` |
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