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Is it expensive to use try-catch blocks even if an exception is never thrown?
...
Let's measure it, shall we?
public abstract class Benchmark {
final String name;
public Benchmark(String name) {
this.name = name;
}
abstract int run(int iterations) throws Throwable;
private BigDecimal time() {
try {
int nextI = 1;
i...
Setting an environment variable before a command in Bash is not working for the second command in a
... process (like the accepted answer) nor will it execute the commands in an extra subshell (like the other answer).
As we get a few regular views, it's probably good to give an alternative to eval that will please everyone, and has all the benefits (and perhaps even more!) of this quick eval “tric...
What is a 'semantic predicate' in ANTLR?
...hing:
grammar Numbers;
// entry point of this parser: it parses an input string consisting of at least
// one number, optionally followed by zero or more comma's and numbers
parse
: number (',' number)* EOF
;
// matches a number that is between 1 and 3 digits long
number
: Digit Digit Di...
How to configure logging to syslog in Python?
...
I add a little extra comment just in case it helps anyone because I found this exchange useful but needed this little extra bit of info to get it all working.
To log to a specific facility using SysLogHandler you need to specify the facili...
Find current directory and file's directory [duplicate]
...h) (returns "the directory name of pathname path")
os.getcwd() (returns "a string representing the current working directory")
os.chdir(path) ("change the current working directory to path")
share
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Line continuation for list comprehensions or generator expressions in python
...t appears at the end of a line, where it either doesn't stand out or needs extra padding, which has to be fixed when line lengths change:
x = very_long_term \
+ even_longer_term_than_the_previous \
+ a_third_term
In such cases, use parens:
x = (very_long_term
+ even_...
How to hash some string with sha256 in Java?
How can I hash some string with sha256 in Java? Does anybody know of any free library for this?
15 Answers
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How do I disable “missing docstring” warnings at a file-level in Pylint?
Pylint throws errors that some of files are missing docstrings. I try and add docstrings to each class, method and function but it seems that Pylint also checks that files should a docstring at the beginning of it. Can i disable this somehow? I would like to be notified of a docstring is missing ins...
What is the function of the push / pop instructions used on registers in x86 assembly?
...e terms. For read-only locals spilled to the stack, the main cost is just extra load uops (sometimes memory operands, sometimes with separate mov loads). For spilled non-const variables, the store-forwarding round trips are a lot of extra latency (an extra ~5c vs. forwarding directly, and the stor...
Python != operation vs “is not”
... but are not identical. (They are not the same object in memory.)
Example: Strings
>>> greeting = "It's a beautiful day in the neighbourhood."
>>> a = unicode(greeting)
>>> b = unicode(greeting)
>>> a is b
False
>>> a == b
True
Note: I use unicode stri...