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Why are const parameters not allowed in C#?
...od type system, a type system where when you say "this variable contains a string" that the variable actually contains a reference to a string (or null). We absolutely do not want to put a C-style "const" modifier into the type system because we don't want the type system to be a lie. We want the ty...
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...
Flexbox Not Centering Vertically in IE
... 2019, the best solution by far is the one by @sergey-fedirko requiring no extra HTML elements and no hard heights ;) This one: stackoverflow.com/a/54796082/134120
– AsGoodAsItGets
Mar 12 '19 at 12:19
...
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
...
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...
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...
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...
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 &&...
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...
Collections.emptyMap() vs new HashMap()
...e this, and does not allow null references:
public ResultSet executeQuery(String query, Map<String, Object> queryParameters);
If you have a query that doesn't take any parameters, it's certainly a bit wasteful to create a HashMap, which involves allocating an array, when you could just pass...