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Span inside anchor or anchor inside span or doesn't matter?
I want to nest span and a tags. Should I
10 Answers
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What's a concise way to check that environment variables are set in a Unix shell script?
...(an empty string) is OK — not exactly what you want, but the alternative and older notation.
The second variant (using :?) requires DEST to be set and non-empty.
If you supply no message, the shell provides a default message.
The ${var?} construct is portable back to Version 7 UNIX and the Bourne ...
How can I generate a list or array of sequential integers in Java?
Is there a short and sweet way to generate a List<Integer> , or perhaps an Integer[] or int[] , with sequential values from some start value to an end value?
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Why Choose Struct Over Class?
...n many circumstances.
Structs are preferable if they are relatively small and copiable because copying is way safer than having multiple references to the same instance as happens with classes. This is especially important when passing around a variable to many classes and/or in a multithreaded env...
Remove an entire column from a data.frame in R
...on't need drop argument cause it always return data.frame from data.frame. And I think this is much better way to localized columns (and only columns) in data.frame (and it's faster). Check: cars[-1] (one col data.frame) or better cars[-(1:2)]: data frame with 0 columns and 50 rows.
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Better to 'try' something and catch the exception or test if it's possible first to avoid an excepti
Should I test if something is valid or just try to do it and catch the exception?
8 Answers
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CharSequence VS String in Java?
Programming in Android, most of the text values are expected in CharSequence .
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What should I name a table that maps two tables together? [closed]
...There are only two hard things in
Computer Science: cache invalidation
and naming things-- Phil Karlton
Coming up with a good name for a table that represents a many-to-many relationship makes the relationship easier to read and understand. Sometimes finding a great name is not trivial but usu...
Returning multiple values from a C++ function
...a C++ function? For example, imagine a function that divides two integers and returns both the quotient and the remainder. One way I commonly see is to use reference parameters:
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What is the difference between tree depth and height?
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The difference between them is that in one case you count number of nodes and in other number of edges on the shortest path between root and concrete node.
Which is which?
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