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How do I avoid capturing self in blocks when implementing an API?
...ied inside the block (we're not doing that) but also they are not automatically retained when the block is retained (unless you are using ARC). If you do this, you must be sure that nothing else is going to try to execute the block after the MyDataProcessor instance is released. (Given the structure...
Visual Studio debugging/loading very slow
...Options -> Debugging -> Symbols
Click on the "..." button and create/select a new folder somewhere on your local computer to store cached symbols. I named mine "Symbol caching" and put it in Documents -> Visual Studio 2012.
Click on "Load all symbols" and wait for the symbols to be download...
How to display the current year in a Django template?
...ration year dropdown with 20 values (starting with the current year). The select values needed to be 2 digits and the display strings 4 digits. To avoid complex template code, I wrote this simple template tag:
@register.filter
def add_current_year(int_value, digits=4):
if digits == 2:
...
Define a lambda expression that raises an Exception
...ur goal is to avoid a def, this obviously doesn't cut it. It does, however allow you to conditionally raise exceptions, e.g.:
y = lambda x: 2*x if x < 10 else raise_(Exception('foobar'))
Alternatively you can raise an exception without defining a named function. All you need is a strong stom...
Elasticsearch query to return all records
I have a small database in Elasticsearch and for testing purposes would like to pull all records back. I am attempting to use a URL of the form...
...
How to style readonly attribute with CSS?
...
w/ IE7 you can still use the selector with jQuery
– ladieu
Apr 30 '14 at 17:55
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show 4 more c...
Repeat each row of data.frame the number of times specified in a column
...es
library(dplyr)
df %>%
slice(rep(seq_len(n()), freq)) %>%
select(-freq)
# var1 var2
#1 a d
#2 b e
#3 b e
#4 c f
#5 c f
#6 c f
seq_len(n()) part can be replaced with any of the following.
df %>% slice(rep(1:nrow(df), freq)) %>% select(-...
Dynamically set local variable [duplicate]
How do you dynamically set local variable in Python (where the variable name is dynamic)?
7 Answers
...
How do I make an attributed string using Swift?
...ng: " Attributed Strings")
myString.append(attrString)
Next we'll just select the "Strings" word, which starts at index 17 and has a length of 7. Notice that this is an NSRange and not a Swift Range. (See this answer for more about Ranges.) The addAttribute method lets us put the attribute key n...
How to implement __iter__(self) for a container object (Python)
...
I normally would use a generator function. Each time you use a yield statement, it will add an item to the sequence.
The following will create an iterator that yields five, and then every item in some_list.
def __iter__(self):
...