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What does “fragment” mean in ANTLR?
...is somewhat akin to an inline function: It makes the grammar more readable and easier to maintain.
A fragment will never be counted as a token, it only serves to simplify a grammar.
Consider:
NUMBER: DIGITS | OCTAL_DIGITS | HEX_DIGITS;
fragment DIGITS: '1'..'9' '0'..'9'*;
fragment OCTAL_DIGITS: '...
Fast check for NaN in NumPy
... to get slower as NaNs get closer to the start of the array. On the other hand, sum's throughput seems constant regardless of whether there are NaNs and where they're located:
In [40]: x = np.random.rand(100000)
In [41]: %timeit np.isnan(np.min(x))
10000 loops, best of 3: 153 us per loop
In [42]:...
What is the default access modifier in Java? [duplicate]
... modifier or no modifier (package-private) just as with top-level classes, and with the same meaning.
Full story you can read here (Which I wrote recently):
http://codeinventions.blogspot.com/2014/09/default-access-modifier-in-java-or-no.html
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SQL Server equivalent to Oracle's CREATE OR REPLACE VIEW
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Alter a view is way better than drop and recreate it. What if you have a lot of existing users security setup for a view, then you would have to recreate all those. This is my approach to this issue.
– jonas
Dec 4 '13 at 11...
Why is \r a newline for Vim?
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For me the point of confusion is that \r and \n mean different things when used is the search pattern and the replacement pattern.
– dlamblin
Dec 4 '12 at 17:09
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How do I compare two strings in Perl?
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See perldoc perlop. Use lt, gt, eq, ne, and cmp as appropriate for string comparisons:
Binary eq returns true if the left argument is stringwise equal to the right argument.
Binary ne returns true if the left argument is stringwise not equal to the right argument....
Why would I make() or new()?
...ents dedicate many paragraphs to explaining the difference between new() and make() , but in practice, you can create objects within local scope and return them.
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How can I list (ls) the 5 last modified files in a directory?
...ed files:
ls -1t | head -5
The -1 (that's a one) says one file per line and the head says take the first 5 entries.
If you want the last 5 try
ls -1t | tail -5
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How to activate an Anaconda environment
...or your environment (so that it gets the right Python from the environment and Scripts\ on Windows).
Imagine you have created an environment called py33 by using:
conda create -n py33 python=3.3 anaconda
Here the folders are created by default in Anaconda\envs, so you need to set the PATH as:
s...
Is it possible to write data to file using only JavaScript?
...to save it on your server then simply pass on the text data to your server and execute the file writing code using some server side language.
To store some information on the client side that is considerably small, you can go for cookies.
Using the HTML5 API for Local Storage.
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