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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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Are lists thread-safe?
... instead of lists and .pop() . Is this because lists are not thread-safe, or for some other reason?
4 Answers
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Concept behind these four lines of tricky C code
... 'k' 0x63 'c' 0x75 'u' 0x53 'S' 0x2B '+' 0x2B '+' 0x43 'C'
This pattern corresponds to the string that you see printed, only backwards. At the same time, the second element of the array becomes zero, providing null terminator, making the string suitable for passing to printf().
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findViewById in Fragment
...which will refer to the ImageView element which I have created in the XML for the Fragment. However, the findViewById method only works if I extend an Activity class. Is there anyway of which I can use it in Fragment as well?
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How can I get a list of build targets in Ant?
...thout having to search through the file manually. Does ant have a command for this - something like ant show-targets - that will make it list all the targets in the build file?
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Join strings with a delimiter only if strings are not null or empty
This feels like it should be simple, so sorry if I'm missing something here, but I'm trying to find a simple way to concatenate only non-null or non-empty strings.
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Convert LocalDate to LocalDateTime or java.sql.Timestamp
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JodaTime
To convert JodaTime's org.joda.time.LocalDate to java.sql.Timestamp, just do
Timestamp timestamp = new Timestamp(localDate.toDateTimeAtStartOfDay().getMillis());
To convert JodaTime's org.joda.time.LocalDateTime to java.sql.Timestamp, just do
Tim...
Common MySQL fields and their appropriate data types
I am setting up a very small MySQL database that stores, first name, last name, email and phone number and am struggling to find the 'perfect' datatype for each field. I know there is no such thing as a perfect answer, but there must be some sort of common convention for commonly used fields such as...
Why use strict and warnings?
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For starters, use strict; (and to a lesser extent, use warnings;) helps find typos in variable names. Even experienced programmers make such errors. A common case is forgetting to rename an instance of a variable when cleaning...
unix - head AND tail of file
...u can simply:
(head; tail) < file.txt
And if you need to uses pipes for some reason then like this:
cat file.txt | (head; tail)
Note: will print duplicated lines if number of lines in file.txt is smaller than default lines of head + default lines of tail.
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