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How to check iOS version?
...system version as an indication of device or OS capabilities. There is usually a more reliable method of checking whether a particular feature or class is available.
Checking for the presence of APIs:
For example, you can check if UIPopoverController is available on the current device using NSCla...
How to make a variadic macro (variable number of arguments)
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The reason for ## before VA_ARGS is that it swallows the preceding comma in case the variable-argument list is empty, eg. FOO("a") expands to printf("a"). This is an extension of gcc (and vc++, maybe), C99 requires at least one argument to be present in place of the elli...
Jasmine JavaScript Testing - toBe vs toEqual
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For primitive types (e.g. numbers, booleans, strings, etc.), there is no difference between toBe and toEqual; either one will work for 5, true, or "the cake is a lie".
To understand the difference between toBe and toEqual, let's imagine three objects.
var a = { bar: 'baz' },
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How to convert R Markdown to PDF?
...late for your needs (like adding there \listoffigures and/or \listoftables etc.) could result in wonderful documents.
– daroczig
Jun 15 '12 at 18:39
3
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How to limit the maximum value of a numeric field in a Django model?
...ormer can be restricted to the number of decimal places stored and the overall number of characters stored, is there any way to restrict it to storing only numbers within a certain range, e.g. 0.0-5.0 ?
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Convert a row of a data frame to vector
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Might have been changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-))
– Andri Signorell
Sep 25 '1...
How can I get a precise time, for example in milliseconds in Objective-C?
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Actually this is precise enough for the general use case.
– logancautrell
Jul 2 '12 at 12:30
4
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Python: avoid new line with print command [duplicate]
...ork on 3.x, you suppress using print('whateverhere', end='') where end normally defaults to '\n'
– Jon Clements♦
Jun 29 '12 at 17:19
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Array versus List: When to use which?
...er - List<T> is one-dimensional; where-as you have have rectangular (etc) arrays like int[,] or string[,,] - but there are other ways of modelling such data (if you need) in an object model.
See also:
How/When to abandon the use of Arrays in c#.net?
Arrays, What's the point?
That said, I ...
What is the syntax rule for having trailing commas in tuple definitions?
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In all cases except the empty tuple the comma is the important thing. Parentheses are only required when required for other syntactic reasons: to distinguish a tuple from a set of function arguments, operator precedence, or to a...