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How do I get the number of elements in a list?
...turns 3.
Explanation
Everything in Python is an object, including lists. All objects have a header of some sort in the C implementation.
Lists and other similar builtin objects with a "size" in Python, in particular, have an attribute called ob_size, where the number of elements in the object is...
How do I correctly clean up a Python object?
...it close() statement is that you have to worry about people forgetting to call it at all or forgetting to place it in a finally block to prevent a resource leak when an exception occurs.
To use the with statement, create a class with the following methods:
def __enter__(self)
def __exit__(self...
“unadd” a file to svn before commit
...Ok, I guess you and I understand this phrase differently: without deleting all the documents. Unfortunately, svn revert does also delete the newly added changes in the working copy, by restoring the lastest HEAD version. I removed my downvote, but I still feel the warning is important.
...
How to disable GCC warnings for a few lines of code
...n GCC and Clang.
Consider the following Makefile
CPPFLAGS:=-std=c11 -W -Wall -pedantic -Werror
.PHONY: all
all: puts
for building the following puts.c source code
#include <stdio.h>
int main(int argc, const char *argv[])
{
while (*++argv) puts(*argv);
return 0;
}
It will not c...
How do I copy directories recursively with gulp?
...c( [ files ], { "base" : "." }) can be used in the structure above to copy all the directories recursively.
If, like me, you may forget this then try:
gulp.copy=function(src,dest){
return gulp.src(src, {base:"."})
.pipe(gulp.dest(dest));
};
...
Where to use EJB 3.1 and CDI?
... together.
EJB >= CDI
Note that EJBs are CDI beans and therefore have all the benefits of CDI. The reverse is not true (yet). So definitely don't get into the habit of thinking "EJB vs CDI" as that logic really translates to "EJB+CDI vs CDI", which is an odd equation.
In future versions of J...
Matplotlib transparent line plots
...
After I plotted all the lines, I was able to set the transparency of all of them as follows:
for l in fig_field.gca().lines:
l.set_alpha(.7)
EDIT: please see Joe's answer in the comments.
...
What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?
...ajority of use cases, but it should be noted that :map, etc. don't work in all modes, exactly, just all the common ones (specifically, normal mode, visual mode, select mode, and operator-pending mode). If you want a mapping to work in insert, command-line, or lang-arg mode, you need to use :map!, et...
What is the difference between save and export in Docker?
... Docker for a couple of days and I already made some images (which was really fun!). Now I want to persist my work and came to the save and export commands, but I don't fully understand them.
...
How can you set class attributes from variable arguments (kwargs) in python
...riable number of arguments and then sets them as class attributes conditionally.
10 Answers
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