大约有 12,000 项符合查询结果（耗时：0.0233秒） [XML]
What's a concise way to check that environment variables are set in a Unix shell script?
...eck it (with version 0.4.1), I get this message:
In script.sh line 13:
: ${FOO:?"The environment variable 'FOO' must be set and non-empty"}
^-- SC2086: Double quote to prevent globbing and word splitting.
Any advice on what I should do in this case?
The short answer is "do as shellcheck suggests...
Why is it possible to recover from a StackOverflowError?
...thrown and why. Since you catch the exception outside of the first call to foo(), the thousands of foo stack frames that filled the stack have all been unwound and most of the stack is free to be used again.
share
|...
How to add pandas data to an existing csv file?
...sv.csv', 'a') as f:
df.to_csv(f, header=False)
If this was your csv, foo.csv:
,A,B,C
0,1,2,3
1,4,5,6
If you read that and then append, for example, df + 6:
In [1]: df = pd.read_csv('foo.csv', index_col=0)
In [2]: df
Out[2]:
A B C
0 1 2 3
1 4 5 6
In [3]: df + 6
Out[3]:
A ...
Finding current executable's path without /proc/self/exe
...../bin/executable — relative to pwd
bin/executable — relative to pwd
./foo — relative to pwd
executable — basename, find in path
bin//executable — relative to pwd, non-canonical
src/../bin/executable — relative to pwd, non-canonical, backtracking
bin/./echoargc — relative to pwd, non-c...
When is the finalize() method called in Java?
...instead:
// try-finally block guarantees execution of termination method
Foo foo = new Foo(...);
try {
// Do what must be done with foo
...
} finally {
foo.terminate(); // Explicit termination method
}
share
...
Can I get the name of the currently running function in JavaScript?
...
For non-anonymous functions
function foo()
{
alert(arguments.callee.name)
}
But in case of an error handler the result would be the name of the error handler function, wouldn't it?
...
Is it possible to perform a 'grep search' in all the branches of a Git project?
...
I found this most useful:
git grep -i foo `git for-each-ref --format='%(refname)' refs/`
You'd need to adjust the last arguments depending on whether you want to only look at remote vs. local branches, i.e.:
git grep -i foo $(git for-each-ref --format='%(refn...
What are the default access modifiers in C#?
...
So for example:
namespace MyCompany
{
class Outer
{
void Foo() {}
class Inner {}
}
}
is equivalent to
namespace MyCompany
{
internal class Outer
{
private void Foo() {}
private class Inner {}
}
}
The one sort of exception to this is maki...
Does JavaScript have “Short-circuit” evaluation?
...
Yes, JavaScript has "short-circuit" evaluation.
if (true == true || foo.foo){
// Passes, no errors because foo isn't defined.
}
Live DEMO
if (false && foo.foo){
// Passes, no errors because foo isn't defined.
}
Live DEMO
...
Only get hash value using md5sum (without filename)
...
How come echo ($(echo -n foo | md5sum)) doesn't work? Errors out bash: syntax error near unexpected token $(echo -n foo | md5sum)'
– lkraav
Aug 26 '15 at 4:42
...