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Java regex email
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Just two counterexamples: webmaster@müller.de (valid and rejected by your example), matteo@78.47.122.114 (my email, valid and rejected by your example.
– Matteo
Nov 21 '11 at 5:58
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Get records with max value for each group of grouped SQL results
...alue for.
You avoid complicated subqueries that try to find the max() etc, and also the problems of returning multiple rows when there are more than one with the same maximum value (as the other answers would do)
Note: This is a mysql-only solution. All other databases I know will throw an SQL synta...
How come an array's address is equal to its value in C?
In the following bit of code, pointer values and pointer addresses differ as expected.
6 Answers
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Split column at delimiter in data frame [duplicate]
... rename it appropriately (the rename function from the reshape package is handy for doing this on the fly) and then rbind it with the existing data frame -- extra effort to get it inserted in place of the previous single column rather than as the first or last columns ...
– Ben...
Comma in C/C++ macro
...an also represent (or occur in) the comparison operators <, >, <= and >=, macro expansion can't ignore commas inside angle brackets like it does within parentheses. (This is also a problem for square brackets and braces, even though those usually occur as balanced pairs.) You can enclo...
Create a pointer to two-dimensional array
...ow they do
uint8_t (*matrix_ptr)[][20] = l_matrix;
If you fix the error and add the address-of operator & like in the following snippet
uint8_t (*matrix_ptr)[][20] = &l_matrix;
Then that one creates a pointer to an incomplete array type of elements of type array of 20 uint8_t. Because ...
Getting all types in a namespace via reflection
... assemblies, including .net's. GetAssemblies will give you all assemblies, and GetAssemblies().SelectMany(t => t.GetTypes()) will give all types (classes, structs etc) from all assemblies.
– nawfal
Jul 10 '14 at 5:42
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Vim: Creating parent directories on save
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augroup BWCCreateDir
autocmd!
autocmd BufWritePre * if expand("<afile>")!~#'^\w\+:/' && !isdirectory(expand("%:h")) | execute "silent! !mkdir -p ".shellescape(expand('%:h'), 1) | redraw! | endif
augroup END
Note the conditions: expand("<afile>")!~#'^\w\+:/' wil...
Delete all but the most recent X files in bash
Is there a simple way, in a pretty standard UNIX environment with bash, to run a command to delete all but the most recent X files from a directory?
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How to create a WPF UserControl with NAMED content
I have a set of controls with attached commands and logic that are constantly reused in the same way. I decided to create a user control that holds all the common controls and logic.
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