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Uppercase Booleans vs. Lowercase in PHP
...only way you can mess things up is by quoting those values, for example:
$foo = false; // FALSE
$bar = "false"; // TRUE
$foo2 = true; // TRUE
$bar2 = "true"; // TRUE
$foo3 = null; // NULL
$bar3 = "null"; // TRUE
Only thing restricting or encouraging you to use upper or lowercase might be ...
What does the star operator mean, in a function call?
...
Just adding a footnote to the textbook answer - before syntactical support arrived, the same functionality was achieved with the built-in apply() function
– Jeremy Brown
May 27 '10 at 14:20
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const vs constexpr on variables
...rameter be declared as const and not as constexpr: ie, would constexpr int foo(S) be executed at compile-time if I call foo(s0) ?
– Matthieu M.
Nov 12 '12 at 16:07
4
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How to backup a local Git repository?
...n my other answer, after Kent Fredric's comment:
$ git bundle create /tmp/foo master
$ git bundle create /tmp/foo-all --all
$ git bundle list-heads /tmp/foo
$ git bundle list-heads /tmp/foo-all
(It is an atomic operation, as opposed to making an archive from the .git folder, as commented by fanta...
PostgreSQL LIKE query performance variations
...en GiST and GIN index
Example query:
SELECT * FROM tbl WHERE col LIKE '%foo%'; -- leading wildcard
SELECT * FROM tbl WHERE col ILIKE '%foo%'; -- works case insensitively as well
Trigrams? What about shorter strings?
Words with less than 3 letters in indexed values still work. The manual:
...
Inserting HTML elements with JavaScript
...chool JavaScript, you could do this:
document.body.innerHTML = '<p id="foo">Some HTML</p>' + document.body.innerHTML;
In response to your comment:
[...] I was interested in declaring the source of a new element's attributes and events, not the innerHTML of an element.
You need t...
How to delete from a text file, all lines that contain a specific string?
...hine (2012 MacBook Air, OS X 10.13.2). Create file: seq -f %f 10000000 >foo.txt. sed d: time sed -i '' '/6543210/d' foo.txt real 0m9.294s. sed !p: time sed -i '' -n '/6543210/!p' foo.txt real 0m13.671s. (For smaller files, the difference is larger.)
– jcsahnwaldt Reinstate M...
g++ undefined reference to typeinfo
...re missing bodies. In your class definition, something like:
virtual void foo();
Should be defined (inline or in a linked source file):
virtual void foo() {}
Or declared pure virtual:
virtual void foo() = 0;
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Compress files while reading data from STDIN
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Yes, gzip will let you do this. If you simply run gzip > foo.gz, it will compress STDIN to the file foo.gz. You can also pipe data into it, like some_command | gzip > foo.gz.
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Copy folder recursively, excluding some folders
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EXCLUDE="foo bar blah jah"
DEST=$1
for i in *
do
for x in $EXCLUDE
do
if [ $x != $i ]; then
cp -a $i $DEST
fi
do...