大约有 23,000 项符合查询结果(耗时:0.0450秒) [XML]

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How to throw a C++ exception

...is is also relevant if the caught objects were "normal" object like: class Base{}; and class Derived : public Base {}... 5) g++ 7.3.0 on Ubuntu 18.04.1 produces a warning that indicates the mentioned issue: In function ‘void illustrateDerivedExceptionCatch()’: item12Linux.cpp:48:2: warnin...
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How to extract the first two characters of a string in shell scripting?

...st efficient method, if you're using the bash shell (and you appear to be, based on your comments), is to use the sub-string variant of parameter expansion: pax> long="USCAGol.blah.blah.blah" pax> short="${long:0:2}" ; echo "${short}" US This will set short to be the first two characters of...
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Is there a way to 'uniq' by column?

... To consider multiple column. Sort and give unique list based on column 1 and column 3: sort -u -t : -k 1,1 -k 3,3 test.txt -t : colon is separator -k 1,1 -k 3,3 based on column 1 and column 3 share ...
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Pythonic way to check if a file exists? [duplicate]

...t. If it does exists, it will print "Ooops" and return None (untested, and based solely on reading the python documentation, so might not be 100% correct). share | improve this answer | ...
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How to set selected item of Spinner by value, not by position?

I have a update view, where I need to preselect the value stored in database for a Spinner. 25 Answers ...
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Why there is no ConcurrentHashSet against ConcurrentHashMap

HashSet is based on HashMap. 9 Answers 9 ...
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Change select box option background color

... I don't know if you've considered it or not but if your application is based on coloring various groupings of items you should probably use the <optgroup> tag coupled with a class for further referencing. For example: <select> <optgroup label="Numbers" class="green"> ...
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Get the last inserted row ID (with SQL statement) [duplicate]

... row (similar to behavior of an update statement that updates a single row based on input of multiple joined rows). – BVernon Jan 6 '19 at 22:56 ...
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AWK: Access captured group from line pattern

...is something I need all the time so I created a bash function for it. It's based on glenn jackman's answer. Definition Add this to your .bash_profile etc. function regex { gawk 'match($0,/'$1'/, ary) {print ary['${2:-'0'}']}'; } Usage Capture regex for each line in file $ cat filename | regex...
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OSGi, Java Modularity and Jigsaw

...ou cannot simply sprinkle modularity on top of an existing non-modular codebase. Making a non-modular codebase into a modular one inevitably requires some refactoring: moving classes into the correct package, replacing direct instantiation with the use of decoupled services, and so on. This makes i...