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What are best practices for validating email addresses on iOS 2.0

... ; "]", or "\" Yes, that means +, ', etc are all legit. share | improve this answer | follow | ...
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What's the difference between using “let” and “var”?

...does not create a property on the global object: var foo = "Foo"; // globally scoped let bar = "Bar"; // globally scoped console.log(window.foo); // Foo console.log(window.bar); // undefined Redeclaration In strict mode, var will let you re-declare the same variable in the same scope while let...
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Is there a difference between foo(void) and foo() in C++ or C?

...tion across both languages and make our headers multilingual (though we usually need to do some more things to the headers to make them truly cross-language; namely, wrap them in an extern "C" if we're compiling C++). share ...
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What is meant by 'first class object'?

...nction literal) if it treats functions as first-class objects. Specifically, this means that the language supports constructing new functions during the execution of a program, storing them in data structures, passing them as arguments to other functions, and returning them as the va...
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How to perform runtime type checking in Dart?

... The instanceof-operator is called is in Dart. The spec isn't exactly friendly to a casual reader, so the best description right now seems to be http://www.dartlang.org/articles/optional-types/. Here's an example: class Foo { } main() { var foo = ne...
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print call stack in C or C++

Is there any way to dump the call stack in a running process in C or C++ every time a certain function is called? What I have in mind is something like this: ...
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How to move a file?

... os.rename(), shutil.move(), or os.replace() All employ the same syntax: import os import shutil os.rename("path/to/current/file.foo", "path/to/new/destination/for/file.foo") shutil.move("path/to/current/file.foo", "path/to/new/destination/for/file.foo") os.replace("p...
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AngularJS - Any way for $http.post to send request parameters instead of JSON?

... return data; } return $.param(data); } }); That way all calls to $http.post will automatically transform the body to the same param format used by the jQuery $.post call. Note you may also want to set the Content-Type header per call or globally like this: $httpProvider.defa...
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What is the exact meaning of IFS=$'\n'?

... Normally bash doesn't interpret escape sequences in string literals. So if you write \n or "\n" or '\n', that's not a linebreak - it's the letter n (in the first case) or a backslash followed by the letter n (in the other two cas...
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How to display pandas DataFrame of floats using a format string for columns?

... As of Pandas 0.17 there is now a styling system which essentially provides formatted views of a DataFrame using Python format strings: import pandas as pd import numpy as np constants = pd.DataFrame([('pi',np.pi),('e',np.e)], columns=['name','value']) C = constants...