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How do I know if a generator is empty from the start?
..., there is no simple way. There are a whole lot of work-arounds.
There really shouldn't be a simple way, because of what generators are: a way to output a sequence of values without holding the sequence in memory. So there's no backward traversal.
You could write a has_next function or maybe eve...
PDO Prepared Inserts multiple rows in single query
... table (fielda, fieldb, ... ) values (?,?...), (?,?...)....
That is basically how we want the insert statement to look like.
Now, the code:
function placeholders($text, $count=0, $separator=","){
$result = array();
if($count > 0){
for($x=0; $x<$count; $x++){
$re...
Is there an expression for an infinite generator?
...
for x in iter(int, 1): pass
Two-argument iter = zero-argument callable + sentinel value
int() always returns 0
Therefore, iter(int, 1) is an infinite iterator. There are obviously a huge number of variations on this particular theme (especially once you add lambda into the mix). One va...
Bash Templating: How to build configuration files from templates with Bash?
...\}/defined $ENV{$1} ? $ENV{$1} : $&/eg' < template.txt
to replace all ${...} strings with corresponding enviroment variables (do not forget to export them before running this script).
For pure bash this should work (assuming that variables do not contain ${...} strings):
#!/bin/bash
while...
How to specify different Debug/Release output directories in QMake .pro file
...ke things even easier to switch around, only define your DESTDIRs conditionally, and then use that value in all your other paths: OBJECTS_DIR = $${DESTDIR}/.obj. Cheers!
– Xavier Holt
Mar 7 '12 at 4:16
...
What does FETCH_HEAD in Git mean?
...it like doing git fetch without arguments (or git remote update), updating all your remote branches, then running git merge origin/<branch>, but using FETCH_HEAD internally instead to refer to whatever single ref was fetched, instead of needing to name things.
...
do N times (declarative syntax)
...based on Array.forEach, without any library, just native vanilla.
To basically call something() 3 times, use:
[1,2,3].forEach(function(i) {
something();
});
considering the following function:
function something(){ console.log('something') }
The outpout will be
something
something
somethi...
Conditional compilation and framework targets
... are a few minor places where code for my project may be able to be drastically improved if the target framework were a newer version. I'd like to be able to better leverage conditional compilation in C# to switch these as needed.
...
What is the best regular expression to check if a string is a valid URL?
...
I wrote my URL (actually IRI, internationalized) pattern to comply with RFC 3987 (http://www.faqs.org/rfcs/rfc3987.html). These are in PCRE syntax.
For absolute IRIs (internationalized):
/^[a-z](?:[-a-z0-9\+\.])*:(?:\/\/(?:(?:%[0-9a-f][0-9a-f]...
Where does Chrome store extensions?
...s local paths, they are left in the place where there are selected from in all Operating Systems.
Ex: If i load a unpacked Extension from E:\Chrome Extension the unpacked Extension is still in the same location
Storage Location for Packed Extensions
Navigate to chrome://version/ and look for Prof...