大约有 43,200 项符合查询结果（耗时：0.0400秒） [XML]
How to map and remove nil values in Ruby
... and I'd expect it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simply:
items.filter_map { |x| process_x url }
"Ruby 2.7 adds Enumerable#filter_map" is a g...
[] and {} vs list() and dict(), which is better?
...
198
In terms of speed, it's no competition for empty lists/dicts:
>>> from timeit import...
Consistency of hashCode() on a Java string
...
102
I can see that documentation as far back as Java 1.2.
While it's true that in general you sho...
How to initialize all members of an array to the same value?
...
1276
Unless that value is 0 (in which case you can omit some part of the initializer
and the corre...
I change the capitalization of a directory and Git doesn't seem to pick up on it
...
11 Answers
11
Active
...
Best way to represent a fraction in Java?
...arable<BigFraction>
{
private static final long serialVersionUID = 1L; //because Number is Serializable
private final BigInteger numerator;
private final BigInteger denominator;
public final static BigFraction ZERO = new BigFraction(BigInteger.ZERO, BigInteger.ONE, true);
public fin...
Multi-line commands in GHCi
...
187
Most of the time, you can rely on type inference to work out a signature for you. In your exam...