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Why does “_” (underscore) match “-” (hyphen)?
...
Because the underscore _ is a wildcard like the percent %, except that it only looks for one character.
SQL pattern matching enables you to use "_" to match any single character and "%" to match an arbitrary number of characters (including zero...
In where shall I use isset() and !empty()
.....) contains some non-empty data.
To answer question 1 :
$str = '';
var_dump(isset($str));
gives
boolean true
Because the variable $str exists.
And question 2 :
You should use isset to determine whether a variable exists ; for instance, if you are getting some data as an array, you migh...
Can you do a partial checkout with Subversion?
...inity for the leaf directories
'''
import os
import getpass
import pysvn
__author__ = "Karl Ostmo"
__date__ = "July 13, 2011"
# =============================================================================
# XXX The os.path.commonprefix() function does not behave as expected!
# See here: http://...
Which $_SERVER variables are safe?
...lue comes from and hence whether it can be trusted for a certain purpose. $_SERVER['HTTP_FOOBAR'] for example is entirely safe to store in a database, but I most certainly wouldn't eval it.
As such, let's divide those values into three categories:
Server controlled
These variables are set by the ...
How do I run all Python unit tests in a directory?
...t contains my Python unit tests. Each unit test module is of the form test_*.py . I am attempting to make a file called all_test.py that will, you guessed it, run all files in the aforementioned test form and return the result. I have tried two methods so far; both have failed. I will show the tw...
Constructor overload in TypeScript
... Box(params) {
if (params === void 0) { params = {}; }
var _a = params.x, x = _a === void 0 ? 0 : _a, _b = params.y, y = _b === void 0 ? 0 : _b, _c = params.height, height = _c === void 0 ? 1 : _c, _d = params.width, width = _d === void 0 ? 1 : _d;
this.x = x;
this.y ...
UTF-8: General? Bin? Unicode?
...
In general, utf8_general_ci is faster than utf8_unicode_ci, but less correct.
Here is the difference:
For any Unicode character set, operations performed using the _general_ci collation are faster than those for the _unicode_ci collatio...
What is the difference between a mutable and immutable string in C#?
...ring str,
[1] class [mscorlib]System.Text.StringBuilder sb)
IL_0000: nop
IL_0001: ldstr "inital value"
IL_0006: stloc.0
IL_0007: ldstr "\nsecond value"
IL_000c: stloc.0
IL_000d: ldstr "\nthird value"
IL_0012: stloc.0
IL_0013: newobj instance void...
Why does this go into an infinite loop?
...mpiled bytecode, as produced by javap -c, with my comments):
8: iload_1 // Remember current value of x in the stack
9: iinc 1, 1 // Increment x (doesn't change the stack)
12: istore_1 // Write remebered value from the stack to x
For comparison, x = ++x:
8: ...
How to read if a checkbox is checked in PHP?
...="value1">
After submitting the form you can check it with:
isset($_POST['test'])
or
if ($_POST['test'] == 'value1') ...
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