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Convert an NSURL to an NSString
...[myURL absoluteString]; But I had met this error and xcode was crashed. -[__NSCFString absoluteString]: unrecognized selector sent to instance 0x791a18e0
– Võ Mai Trinh
Jun 22 '15 at 9:39
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Fastest way to check if a string matches a regexp in ruby?
...y
require 'benchmark'
str = "aacaabc"
re = Regexp.new('a+b').freeze
N = 4_000_000
Benchmark.bm do |b|
b.report("str.match re\t") { N.times { str.match re } }
b.report("str =~ re\t") { N.times { str =~ re } }
b.report("str[re] \t") { N.times { str[re] } }
b.report("re =~ str...
How does Rails keep track of which migrations have run for a database?
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Rails creates a table in your database called schema_migrations to keep track of which migrations have run.
The table contains a single column, version. When Rails runs a migration, it takes the leading digits in the migration's file name and inserts a row for that "version",...
What are the options for storing hierarchical data in a relational database? [closed]
...s a result, most people end up having to settle for one or the other especially if there are more than, say, a lousy 100,000 nodes or so. Using the push stack method can take a whole day to do the conversion on what MLM'ers would consider to be a small million node hierarchy.
I thought I'd give Ce...
How to fix Python indentation
...py script that you find in the Tools/scripts/ directory of your Python installation:
Change Python (.py) files to use
4-space indents and no hard tab
characters. Also trim excess spaces
and tabs from ends of lines, and
remove empty lines at the end of
files. Also ensure the last line ...
Hide files with certain extension in Sublime Text Editor?
is it possible to hide all the files with certain extension from the sidebar (lateral nav bar) in Sublime Text Editor 3?
2 ...
How do I get the currently displayed fragment?
...t the currently displayed Fragment instance, not iteratively check through all fragments and then decide which fragment is now displayed on the screen. I think your answer needs my code to iteratively check each of my fragments, and find out the visible one ...
– Leem.fin
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How to use/install gcc on Mac OS X 10.8 / Xcode 4.4
... Apple LLVM version 6.0 (clang-600.0.51) (based on LLVM 3.5svn) Target: x86_64-apple-darwin14.0.0 Thread model: posix So am I using gcc?
– Thomas
Dec 14 '14 at 16:11
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How do I test a private function or a class that has private methods, fields or inner classes?
...mework.
@Jailbreak Foo foo = new Foo();
// Direct, *type-safe* access to *all* foo's members
foo.privateMethod(x, y, z);
foo.privateField = value;
This way your code remains type-safe and readable. No design compromises, no overexposing methods and fields for the sake of tests.
If you have...
Why are Oracle table/column/index names limited to 30 characters?
..., but there is always a case that turns up where we hit this limit - especially in naming foreign keys.
10 Answers
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