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How to set a value of a variable inside a template code?
... self.new_val
return ''
import re
@register.tag
def setvar(parser,token):
# This version uses a regular expression to parse tag contents.
try:
# Splitting by None == splitting by spaces.
tag_name, arg = token.contents.split(None, 1)
except ValueError:
rai...
How do I trim leading/trailing whitespace in a standard way?
... pointer to a substring of the original string.
// If the given string was allocated dynamically, the caller must not overwrite
// that pointer with the returned value, since the original pointer must be
// deallocated using the same allocator with which it was allocated. The return
// value must N...
Difference between ProcessBuilder and Runtime.exec()
...of strings or a single string. The single-string overloads of exec() will tokenise the string into an array of arguments, before passing the string array onto one of the exec() overloads that takes a string array. The ProcessBuilder constructors, on the other hand, only take a varargs array of str...
Python List vs. Array - when to use?
...discontiguous and sparse arrays, and I think some pluggable strategies for allocating memory for large arrays... some of these advanced features will make it user less memory, while others will improve performance by using more memory.
– Dan Lenski
Oct 29 '14 a...
Java heap terminology: young, old and permanent generations?
...lowing.
Eden Space (heap): The pool from which memory is initially allocated
for most objects.
Survivor Space (heap): The pool containing objects that have survived
the garbage collection of the Eden
space.
Tenured Generation (heap): The pool containing objects that have existed
...
UITextfield leftView/rightView padding on iOS7
...:UITextFieldViewModeUnlessEditing];
self.leftView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"textfield_edit_icon.png"]];
}
return self;
}
You may have to import #import <QuartzCore/QuartzCore.h>
Add the rightViewRectForBounds method above
In Interface Builder...
How far can memory leaks go?
I've run into memory leaks many times. Usually when I'm malloc -ing like there's no tomorrow, or dangling FILE * s like dirty laundry. I generally assume (read: hope desperately) that all memory is cleaned up at least when the program terminates. Are there any situations where leaked memory won't ...
What exactly does an #if 0 … #endif block do?
...
When the preprocessor sees #if it checks whether the next token has a non-zero value. If it does, it keeps the code around for the compiler. If it doesn't, it gets rid of that code so the compiler never sees it.
If someone says #if 0 they are effectively commenting out the code s...
Adding a simple UIAlertView
...u want the alert to show, do this:
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"ROFL"
message:@"Dee dee doo doo."
delegate:self
...
In what cases do I use malloc and/or new?
I see in C++ there are multiple ways to allocate and free data and I understand that when you call malloc you should call free and when you use the new operator you should pair with delete and it is a mistake to mix the two (e.g. Calling free() on something that was created with the new ...