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Best practices/performance: mixing StringBuilder.append with String.concat
I'm trying to understand what the best practice is and why for concatenating string literals and variables for different cases. For instance, if I have code like this
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Finding a substring within a list in Python [duplicate]
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All the answers work but they always traverse the whole list. If I understand your question, you only need the first match. So you don't have to consider the rest of the list if you found your first match:
mylist = ['abc123', 'def456', 'ghi789']
sub = 'abc'
next((s for s in mylist if sub in s), No...
How to convert std::string to LPCSTR?
...: pointer to null terminated char string of char (often a buffer is passed and used as an 'output' param)
LPCWSTR: pointer to null terminated string of const wchar_t
LPWSTR: pointer to null terminated string of wchar_t (often a buffer is passed and used as an 'output' param)
To "convert" a std::s...
Is there a reason for C#'s reuse of the variable in a foreach?
...way that makes it highly prone to an error that is often difficult to find and debug, while producing no perceivable benefits.
Your criticism is entirely justified.
I discuss this problem in detail here:
Closing over the loop variable considered harmful
Is there something you can do with for...
How do you rotate a two dimensional array?
...e. Printing the matrix is the same complexitiy
– Alejandro
Aug 4 '15 at 20:34
6
For a -90 degrees...
Can the Unix list command 'ls' output numerical chmod permissions?
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For creating it as an alias (example below: 'cls' command), use: alias cls="ls -l | awk '{k=0;for(i=0;i<=8;i++)k+=((substr(\$1,i+2,1)~/[rwx]/)*2^(8-i));if(k)printf(\"%0o \",k);print}'"
– danger89
Mar 6 '14 at 16:15
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how to check the dtype of a column in python pandas
I need to use different functions to treat numeric columns and string columns. What I am doing now is really dumb:
6 Answer...
RegEx: Grabbing values between quotation marks
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([""']) match a quote; ((?=(\\?))\2.) if backslash exists, gobble it, and whether or not that happens, match a character; *? match many times (non-greedily, as to not eat the closing quote); \1 match the same quote that was use for opening.
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How to efficiently compare two unordered lists (not sets) in Python?
... Hey @Raymond, I recently encountered this question on an interview and I used sorted(), admittedly not knowing about Counter. The interviewer insisted there was a more efficient method and clearly I drew a blank. After extensive testing in python 3 with the timeit module, sorted consisten...
Hibernate vs JPA vs JDO - pros and cons of each? [closed]
I'm familiar with ORM as a concept, and I've even used nHibernate several years ago for a .NET project; however, I haven't kept up with the topic of ORM in Java and haven't had a chance to use any of these tools.
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