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What characters are allowed in an email address?
... not appear consecutively unless quoted (e.g. John..Doe@example.com is not allowed but "John..Doe"@example.com is allowed);
space and "(),:;<>@[\] characters are allowed with restrictions (they are only allowed inside a quoted string, as described in the paragraph below, and in addition, a b...
How to check that an object is empty in PHP?
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empty doesn't actually check if an array is empty, empty($var) equivalent to (!isset($var) || !$var). You can replace your empty($arr)s with !$arr since array() == FALSE
– Timothy Zorn
Aug 20 '15 at 18:35...
PyPy — How can it possibly beat CPython?
... an object can save you the need to do multiple pointer dereferences to finally arrive at the method you want to call.
Q2. Which Python implementation was used to implement PyPy?
The PyPy interpreter is implemented in RPython which is a statically typed subset of Python (the language and not the ...
What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?
...ajority of use cases, but it should be noted that :map, etc. don't work in all modes, exactly, just all the common ones (specifically, normal mode, visual mode, select mode, and operator-pending mode). If you want a mapping to work in insert, command-line, or lang-arg mode, you need to use :map!, et...
How to do what head, tail, more, less, sed do in Powershell? [closed]
...an above option
gc log.txt | more # or less if you have it installed
gc log.txt | %{ $_ -replace '\d+', '($0)' } # sed
This works well enough for small files, larger ones (more than a few MiB) are probably a bit slow.
The PowerShell Community Extensions include some cmdlets fo...
Navigation in django
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I like this idea a lot, especially for flexibility, but it comes with the less-DRY trade-off. I did start using this in a site though.
– anonymous coward
Sep 22 '09 at 14:47
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Laravel Eloquent Sum of relation's column
...The documentation is a little light for some of the Collection methods but all the query builder aggregates are seemingly available besides avg() that can be found at http://laravel.com/docs/queries#aggregates.
share
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Heap vs Binary Search Tree (BST)
... 1
Create worst n log(n) n
Delete worst log(n) log(n)
All average times on this table are the same as their worst times except for Insert.
*: everywhere in this answer, BST == Balanced BST, since unbalanced sucks asymptotically
**: using a trivial modification explained in thi...
SQL query for finding records where count > 1
... a user ID, an account number, a ZIP code and a date. I would like to find all records for all users that have more than one payment per day with the same account number.
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What is the use of a private static variable in Java?
... as ClassName.varName . I am also aware that static members are shared by all instances of a class and are not reallocated in each instance.
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