大约有 42,000 项符合查询结果（耗时：0.0467秒） [XML]
How to create abstract properties in python abstract classes
...
3 Answers
3
Active
...
Reverse Range in Swift
...
Update For latest Swift 3 (still works in Swift 4)
You can use the reversed() method on a range
for i in (1...5).reversed() { print(i) } // 5 4 3 2 1
Or stride(from:through:by:) method
for i in stride(from:5,through:1,by:-1) { print(i) } // 5 4...
How to print number with commas as thousands separators?
... commas as thousands separators. For example, I want to show the number 1234567 as 1,234,567 . How would I go about doing this? I have seen many examples on Google, but I am looking for the simplest practical way.
...
typedef fixed length array
I have to define a 24-bit data type.I am using char[3] to represent the type. Can I typedef char[3] to type24 ? I tried it in a code sample. I put typedef char[3] type24; in my header file. The compiler did not complain about it. But when I defined a function void foo(type24 val) {} in my C...
Why is address zero used for the null pointer?
...
|
edited May 3 '10 at 17:44
answered May 3 '10 at 17:22
...
Return multiple values in JavaScript?
...
1380
No, but you could return an array containing your values:
function getValues() {
return [...
Search for string and get count in vi editor
...
|
edited Jun 3 '15 at 9:51
Martin Tournoij
22.1k1717 gold badges8585 silver badges116116 bronze badges
...
rails 3 validation on uniqueness on multiple attributes
I use Rails 3.0.0.beta4
3 Answers
3
...
Paste multiple columns together
...
# your starting data..
data <- data.frame('a' = 1:3, 'b' = c('a','b','c'), 'c' = c('d', 'e', 'f'), 'd' = c('g', 'h', 'i'))
# columns to paste together
cols <- c( 'b' , 'c' , 'd' )
# create a new column `x` with the three columns collapsed together
data$x <- apply( d...
Javascript and regex: split string and keep the separator
...1
JonJon
383k6868 gold badges674674 silver badges755755 bronze badges
...