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Why switch is faster than if
...
Because there are special bytecodes that allow efficient switch statement evaluation when there are a lot of cases.
If implemented with IF-statements you would have a check, a jump to the next clause, a check, a jump to the next clause and so on. Wit...
What does __FILE__ mean in Ruby?
I see this all the time in Ruby:
4 Answers
4
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Match whitespace but not newlines
...+0009 CHARACTER TABULATION
U+0020 SPACE
U+00A0 NO-BREAK SPACE (not matched by \s)
U+1680 OGHAM SPACE MARK
U+2000 EN QUAD
U+2001 EM QUAD
U+2002 EN SPACE
U+2003 EM SPACE
U+2004 THREE-PER-EM SPACE
U+2005 FOUR-PER-EM SPACE
U+2006 SIX-PER-EM SPACE
U+2007 FIGURE SPACE
U+2008 PUNCTUATION SPACE
U+2009 THIN...
Use grep --exclude/--include syntax to not grep through certain files
...hat the star is escaped with a backslash to prevent it from being expanded by the shell (quoting it, such as --include="*.{cpp,h}", would work just as well). Otherwise, if you had any files in the current working directory that matched the pattern, the command line would expand to something like gr...
How can I detect if this dictionary key exists in C#?
...["HomeStreet"] = entry;
}
Update 2: here is the working code (compiled by question asker)
PhysicalAddressEntry entry;
PhysicalAddressKey key = PhysicalAddressKey.Home;
if (c.PhysicalAddresses.TryGetValue(key, out entry))
{
if (entry.Street != null)
{
row["HomeStreet"] = entry.St...
Fluid width with equally spaced DIVs
...any arbitrary number of child divs without adding a boxN class to each one by changing
.box1, .box2, .box3, .box4 { ...
to
#container > div { ...
This selects any div that is the first child of the #container div, and no others below it. To generalize the background colors, you can use the ...
Remove directory from remote repository after adding them to .gitignore
...t push origin master
I advise you to check the files to be deleted first by running the below statement:
git ls-files -i --exclude-from=.gitignore
I was using a default .gitignore file for visual studio and I noticed that it was removing all log and bin folders in the project which was not my i...
How to check if a database exists in SQL Server?
... data type. COLUMN_PRIVILEGES Every column with a privilege granted to or by the current user in the current database. COLUMNS Lists every column in the system CONSTRAINT_COLUMN_USAGE Every column that has a constraint defined on it. CONSTRAINT_TABLE_USAGE Every table that has a constraint defin...
SQL NVARCHAR and VARCHAR Limits
...(max) can store up to (and beyond sometimes) 2GB of data (1 billion double byte characters).
From nchar and nvarchar in Books online the grammar is
nvarchar [ ( n | max ) ]
The | character means these are alternatives. i.e. you specify either n or the literal max.
If you choose to specify a specifi...
What does collation mean?
... American), collation may be a pretty simple matter consisting of ordering by the ASCII code.
Once you get into those strange European languages with all their accents and other features, collation changes. For example, though the different accented forms of a may exist at disparate code points, th...