rfc:closures
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| rfc:closures [2009/12/15 22:40] – Fix list numbering rquadling | rfc:closures [2017/09/22 13:28] (current) – external edit 127.0.0.1 | ||
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| Note: str_replace also accepts arrays as a third parameter so this example may be a bit useless. But imagine you want to do a more complex operation than simple search and replace. | Note: str_replace also accepts arrays as a third parameter so this example may be a bit useless. But imagine you want to do a more complex operation than simple search and replace. | ||
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| ===== Common misconceptions ===== | ===== Common misconceptions ===== | ||
| - Lambda functions / closures are **not** a way of dynamically extending classes by additional methods at runtime. There are several other possibilities to do this, including the already present _ _call semantic. | - Lambda functions / closures are **not** a way of dynamically extending classes by additional methods at runtime. There are several other possibilities to do this, including the already present _ _call semantic. | ||
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| - PHP's notion of scope is quite different than the notion of scope other languages define. Combine this with variable variables ($$var) and it becomes clear that automatically detecting which variables from the outer scope are referenced inside are closure is impossible. Also, since for example global variables are not visible inside functions either by default, automatically making the parent scope available would break with the current language concept PHP follows. | - PHP's notion of scope is quite different than the notion of scope other languages define. Combine this with variable variables ($$var) and it becomes clear that automatically detecting which variables from the outer scope are referenced inside are closure is impossible. Also, since for example global variables are not visible inside functions either by default, automatically making the parent scope available would break with the current language concept PHP follows. | ||
rfc/closures.txt · Last modified: 2017/09/22 13:28 by 127.0.0.1