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How to pass command line arguments to a shell alias? [duplicate]
...osted for other shells, in Bash the following works:
alias blah='function _blah(){ echo "First: $1"; echo "Second: $2"; };_blah'
Running the following:
blah one two
Gives the output below:
First: one
Second: two
shar...
How to export table as CSV with headings on Postgresql?
...
COPY products_273 TO '/tmp/products_199.csv' WITH (FORMAT CSV, HEADER);
as described in the manual.
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'float' vs. 'double' precision
...54 bindings) is normative, but only in effect if an implementation defines __STDC_IEC_559__. An implementation that does not define that macro is free not to conform to IEEE-754.
– Stephen Canon
Feb 24 '11 at 0:06
...
How do I change the string representation of a Python class? [duplicate]
...
The closest equivalent to Java's toString is to implement __str__ for your class. Put this in your class definition:
def __str__(self):
return "foo"
You may also want to implement __repr__ to aid in debugging.
See here for more information:
Special Method Names - Basic Cu...
Print a list in reverse order with range()?
... memory for the whole list? range can return an object that implements the __reversed__ method that allows efficient reverse iteration?
– avmohan
Aug 5 '17 at 10:45
...
How can I match a string with a regex in Bash?
...n the comment above, We need to store the regex on a var
The variable BASH_REMATCH is set after you match the expression, and ${BASH_REMATCH[n]} will match the nth group wrapped in parentheses ie in the following ${BASH_REMATCH[1]} = "compressed" and ${BASH_REMATCH[2]} = ".gz"
if [[ "compressed.gz...
Is it better to use std::memcpy() or std::copy() in terms to performance?
... of std::copy over memcpy: 2.99%
My compiler is gcc 4.6.3 on Fedora 16 x86_64. My optimization flags are -Ofast -march=native -funsafe-loop-optimizations.
Code for my SHA-2 implementations.
I decided to run a test on my MD5 implementation as well. The results were much less stable, so I decided t...
What does “dereferencing” a pointer mean?
...hat can be written to, then you can do things like this:
int x = 2;
int* p_x = &x; // Put the address of the x variable into the pointer p_x
*p_x = 4; // Change the memory at the address in p_x to be 4
assert(x == 4); // Check x is now 4
Above, you must have known at compile time that ...
Vim: insert the same characters across multiple lines
...e (Ctrlv).
Press j three times (or 3j).
Press I (capital i).
Type in vendor_. Note: It will only update the screen in the first line - until Esc is pressed (6.), at which point all lines will be updated.
Press Esc.
An uppercase I must be used rather than a lowercase i, because the lowercase i is...
python design patterns [closed]
...for their existence.
It's nothing more than
class Null(object):
def __init__(self, *args, **kwargs):
"Ignore parameters."
return None
def __call__(self, *args, **kwargs):
"Ignore method calls."
return self
def __getattr__(self, mname):
"Ignore...