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Extracting substrings in Go
...confused by the working of slices and the string storage format, which is different from what you have in C.
any slice in Go stores the length (in bytes), so you don't have to care about the cost of the len operation : there is no need to count
Go strings aren't null terminated, so you don't have ...
If string is empty then return some default value
Often I need to check if some value is blank and write that "No data present" like that:
6 Answers
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How do RVM and rbenv actually work?
...d. Every Bash command that rbenv runs will be written to your terminal.
Now, rbenv is just concerned with switching versions, but a thriving ecosystem of plugins will help you do everything from installing Ruby to setting up your environment, managing "gemsets" and even automating bundle exec.
I...
Dependent DLL is not getting copied to the build output folder in Visual Studio
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I found that if ProjectX referenced the abc.dll but didn't directly use any of the types DEFINED in abc.dll, then abc.dll would NOT be copied to the main output folder. (It would be copied to the ProjectX output folder, to make it extra-c...
Rails detect if request was AJAX
In my action I wish to only respond with processing if it was called from an AJAX request. How do I check?
5 Answers
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Get file size, image width and height before upload
... document.getElementById('preview');
const readImage = file => {
if ( !(/^image\/(png|jpe?g|gif)$/).test(file.type) )
return EL_preview.insertAdjacentHTML('beforeend', `Unsupported format ${file.type}: ${file.name}<br>`);
const img = new Image();
img.addEventListener('lo...
Using isKindOfClass with Swift
I'm trying to pick up a bit of Swift lang and I'm wondering how to convert the following Objective-C into Swift:
5 Answers
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How is pattern matching in Scala implemented at the bytecode level?
... explored with a disassembler but the short answer is that it's a bunch of if/elses where the predicate depends on the pattern
case Sum(l,r) // instance of check followed by fetching the two arguments and assigning to two variables l and r but see below about custom extractors
case "hello" // equa...
How to print a number with commas as thousands separators in JavaScript
...
max-height: 100% !important;
}
@t.j.crowder pointed out that now that JavaScript has lookbehind (support info), it can be solved in the regular expression itself:
function numberWithCommas(x) {
return x.toString().replace(/\B(?<!\.\d*)(?=(\d{3})+(?!\d))/g, ",");
}
functio...
Techniques for Tracing Constraints
... b ~ sup,
SyntacticN (a -> (a -> b) -> b) fi,
_)
=> a -> (a -> b) -> a
share = sugarSym Let
The key is to use type hole among constraints: _ => your difficult type
share
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