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Installing Ruby Gem in Windows
...uby 2.0.0p353 (2013-11-22) [i386-mingw32]
For Ruby 2.4 or later, run the extra installation at the end to install the DevelopmentKit. If you forgot to do that, run ridk install in your windows console to install it.
For earlier versions:
Download and install DevelopmentKit from the same downloa...
What programming practice that you once liked have you since changed your mind about? [closed]
...ian notation (both Forms and Systems).
I used to prefix everything. strSomeString or txtFoo.
Now I use someString and textBoxFoo. It's far more readable and easier for someone new to come along and pick up. As an added bonus, it's trivial to keep it consistant -- camelCase the control and append a u...
Non-Relational Database Design [closed]
...DBs are a massive win, and the drawbacks of less flexible queries and some extra code for data validation seems a small price to pay.
Have you hit your head against anything that seems impossible?
Not yet. Map/reduce as a means of querying a database is unfamiliar, and requires a lot more thinking...
WHERE vs HAVING
...ect_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+-------+---------------+-------+---------+------+------+--------------------------+
| 1 | SIMPLE | table | range | value | value | 4 | NULL | 5 | U...
Deleting all files in a directory with Python
... list of file names which end it '.bak'. The elements of the list are just strings.
Then you could use os.unlink to remove the files. (PS. os.unlink and os.remove are synonyms for the same function.)
#!/usr/bin/env python
import glob
import os
directory='/path/to/dir'
os.chdir(directory)
files=glo...
Can we omit parentheses when creating an object using the “new” operator?
... making a mistake you should use (new Object).func(). But I consider using extra parenthesis and extra equal signs, as in == vs ===, a bad excuse for not learning your language.
– Jean Vincent
Jun 2 '17 at 12:26
...
What is the difference between List (of T) and Collection(of T)?
...s that it is returning a new instance. Note that for e.g. a Dictionary<string, List<string>> to return List<string> is just fine, since the dictionary's state only encapsulates the identities of the lists therein, rather than their contents.
– supercat
...
Finish all previous activities
...eturn you to home screen finishing all the other activites. You can add an extra in the intent and read that in the home screen activity and finish it also (maybe launch login screen again from there or something).
I am not sure but you can also try going to login with this flag. I don't know how t...
Difference between single and double square brackets in Bash
...nsion.
expr a \< b > /dev/null: POSIX equivalent², see: How to test strings for lexicographic less than or equal in Bash?
&& and ||
[[ a = a && b = b ]]: true, logical and
[ a = a && b = b ]: syntax error, && parsed as an AND command separator cmd1 &&...
Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...' the matrix.
#'
#' @param data data.frame: input data
#' @param rowtitle string: row-dimension; name of the column in data, which distinct values should be used as row names in the output matrix
#' @param coltitle string: col-dimension; name of the column in data, which distinct values should be u...