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Why is this program valid? I was trying to create a syntax error
...bar)
to be written as
new Foo $bar
So that means
Syntax error ! exit 0;
is the same as
error->Syntax(! exit 0);
or
error->Syntax(!exit(0));
Not only is it valid syntax, it doesn't result in a run-time error because the first thing executed is exit(0).
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Anonymous recursive PHP functions
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answered Mar 19 '10 at 20:03
Derek HDerek H
10.2k66 gold badges3232 silver badges3838 bronze badges
...
How can I add a help method to a shell script?
...
here's an example for bash:
usage="$(basename "$0") [-h] [-s n] -- program to calculate the answer to life, the universe and everything
where:
-h show this help text
-s set the seed value (default: 42)"
seed=42
while getopts ':hs:' option; do
case "$option" i...
A regex to match a substring that isn't followed by a certain other substring
...--------------------
.* any character except \n (0 or more times
(matching the most amount possible))
--------------------------------------------------------------------------------
bar 'bar'
---------------------------...
How do you add an array to another array in Ruby and not end up with a multi-dimensional result?
...note the asterisk, and that a2 is the receiver
or splice:
a1[a1.length, 0] = a2
a1[a1.length..0] = a2
a1.insert(a1.length, *a2)
or append and flatten:
(a1 << a2).flatten! # a call to #flatten instead would return a new array
...
Applying function with multiple arguments to create a new pandas column
...n:
>>> import numpy as np
>>> df = pd.DataFrame({"A": [10,20,30], "B": [20, 30, 10]})
>>> df['new_column'] = np.multiply(df['A'], df['B'])
>>> df
A B new_column
0 10 20 200
1 20 30 600
2 30 10 300
or vectorize arbitrary func...
String formatting in Python 3
...ing a single argument twice (as @Burhan Khalid noted in the comments):
"({0.goals} goals, ${0.penalties})".format(self)
Explaining:
{} means just the next positional argument, with default format;
{0} means the argument with index 0, with default format;
{:d} is the next positional argument, wi...
Initializing a two dimensional std::vector
...
208
Use the std::vector::vector(count, value) constructor that accepts an initial size and a defaul...
JavaScript seconds to time string with format hh:mm:ss
...tring.prototype.toHHMMSS = function () {
var sec_num = parseInt(this, 10); // don't forget the second param
var hours = Math.floor(sec_num / 3600);
var minutes = Math.floor((sec_num - (hours * 3600)) / 60);
var seconds = sec_num - (hours * 3600) - (minutes * 60);
if (hours &...
Check whether a string contains a substring
...|
edited Dec 15 '15 at 9:40
answered Sep 2 '11 at 12:21
Eug...