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What is HEAD in Git?
You see the Git documentation saying things like
21 Answers
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How to know if an object has an attribute in Python
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Try hasattr():
if hasattr(a, 'property'):
a.property
EDIT: See zweiterlinde's answer below, who offers good advice about asking forgiveness! A very pythonic approach!
The general practice in python is that, if the property is likely to be there most of the time, simply call it ...
Why doesn't JUnit provide assertNotEquals methods?
Does anybody know why JUnit 4 provides assertEquals(foo,bar) but not assertNotEqual(foo,bar) methods?
11 Answers
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How slow are .NET exceptions?
...g exceptions revolves around them being slow while the other side claims (with benchmark test) that the speed is not the issue. I've read numerous blogs, articles, and posts pertaining one side or the other. So which is it?
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Will strlen be calculated multiple times if used in a loop condition?
I'm not sure if the following code can cause redundant calculations, or is it compiler-specific?
18 Answers
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Find the last element of an array while using a foreach loop in PHP
I am writing a SQL query creator using some parameters. In Java, it's very easy to detect the last element of an array from inside the for loop by just checking the current array position with the array length.
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Runnable with a parameter?
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Well it's been almost 9 years since I originally posted this and to be honest, Java has made a couple improvements since then. I'll leave my original answer below, but there's no need for people to do what is in it. 9 years ago, d...
Makefiles with source files in different directories
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The traditional way is to have a Makefile in each of the subdirectories (part1, part2, etc.) allowing you to build them independently. Further, have a Makefile in the root directory of the project which builds everything. The "root"...
Performance surprise with “as” and nullable types
I'm just revising chapter 4 of C# in Depth which deals with nullable types, and I'm adding a section about using the "as" operator, which allows you to write:
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What is Weak Head Normal Form?
...ed out, head normal form does not apply to Haskell, so I will not consider it here.
Normal form
An expression in normal form is fully evaluated, and no sub-expression could be evaluated any further (i.e. it contains no un-evaluated thunks).
These expressions are all in normal form:
42
(2, "hello...