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What does the `forall` keyword in Haskell/GHC do?
I'm beginning to understand how the forall keyword is used in so-called "existential types" like this:
8 Answers
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Force DOM redraw/refresh on Chrome/Mac
...e DOM inspector is often enough to get it to realize the error of its ways and redraw correctly, so it's provably the case that the markup is good. This happens frequently (and predictably) enough in a project I'm working on that I've put code in place to force a redraw in certain circumstances.
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How to enter quotes in a Java string?
I want to initialize a String in Java, but that string needs to include quotes; for example: "ROM" . I tried doing:
10 Ans...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...ies, levels=c(levels(iris$Species), "empty_level"))
# Species is a factor and empty groups are included in the output
iris %>% group_by(Species, .drop=FALSE) %>% tally
#> Species n
#> 1 setosa 50
#> 2 versicolor 50
#> 3 virginica 50
#> 4 empty_level ...
jQuery Ajax error handling, show custom exception messages
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This is still the correct way of doing this after 2 years and a half... :) I went a little further and actually return my own error JSON object that can handle single or multiple errors, quite good for server-side form validation.
– AlexCode
Ju...
Extract substring in Bash
...he form someletters_12345_moreleters.ext , I want to extract the 5 digits and put them into a variable.
22 Answers
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Why is a combiner needed for reduce method that converts type in java 8
I'm having trouble fully understanding the role that the combiner fulfils in Streams reduce method.
4 Answers
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Grant execute permission for a user on all stored procedures in database?
I generated script from old database, created a new database and imported all data from old database. So far so good, however, no user has execute rights for stored procedures. I know I can use
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C libcurl get output into a string
...de that passes a buffer struct string {*ptr; len} to the callback function and grows that buffer on each call using realloc().
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <curl/curl.h>
struct string {
char *ptr;
size_t len;
};
void init_string(s...
Why does Math.Round(2.5) return 2 instead of 3?
...ug. C# is the language - it doesn't decide how Math.Round is implemented.
And secondly, no - if you read the docs, you'll see that the default rounding is "round to even" (banker's rounding):
Return ValueType: System.DoubleThe integer nearest a. If the
fractional component of a is halfway
b...