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Setting an environment variable before a command in Bash is not working for the second command in a
... process (like the accepted answer) nor will it execute the commands in an extra subshell (like the other answer).
As we get a few regular views, it's probably good to give an alternative to eval that will please everyone, and has all the benefits (and perhaps even more!) of this quick eval “tric...
How can I sanitize user input with PHP?
...at you should do, to avoid problems, is quite simple: whenever you embed a string within foreign code, you must escape it, according to the rules of that language. For example, if you embed a string in some SQL targeting MySQL, you must escape the string with MySQL's function for this purpose (mysql...
Python's many ways of string formatting — are the older ones (going to be) deprecated?
Python has at least six ways of formatting a string:
5 Answers
5
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How do you access the matched groups in a JavaScript regular expression?
I want to match a portion of a string using a regular expression and then access that parenthesized substring:
22 Answers...
How to “perfectly” override a dict?
...r that ensures keys are passed into the dict in lowercase form if they are strings.
If I override __getitem__/__setitem__, then get/set don't work. How do I make them work? Surely I don't need to implement them individually?
Well, implementing them each individually is the downside to this app...
Read an Excel file directly from a R script
...d to look at your numbers" ... what is the issue with "-" fields? does na.strings="-" address the problem? How many of these issues are generic and how many of them (e.g. numeric fields with commas) can be addressed with other tools such as XLConnect ...?
– Ben Bolker
...
Event on a disabled input
...vidual container of its own, if they aren't already laid out that way - an extra <span> or a <div>, say - just to make it easy to distinguish which disabled input was clicked).
The downside is that this trick unfortunately won't works for older browsers that don't support the pointer-...
Ruby replace string with captured regex pattern
...only seem to be interested in the capture group, note that you can index a string with a regex:
"foo"[/oo/]
#=> "oo"
"Z_123: foobar"[/^Z_.*(?=:)/]
#=> "Z_123"
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counting number of directories in a specific directory
... use shell_exec() function to execute command line and return results to a string. i.e. $dirCount = shell_exec('ls -l | grep -c ^d');
– gigabyte
Apr 13 '19 at 20:44
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When do we need curly braces around shell variables?
...er, the {} in ${} are useful if you want to expand the variable foo in the string
"${foo}bar"
since "$foobar" would instead expand the variable identified by foobar.
Curly braces are also unconditionally required when:
expanding array elements, as in ${array[42]}
using parameter expansion oper...