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Haskell error parse error on input `='
I'm new to Haskell m>and m> after starting ghci I tried:
4 Answers
4
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Test for equalitm>y m> among all elements of a single vector
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I use this method, which compares the min m>and m> the max, after dividing bm>y m> the mean:
# Determine if range of vector is FP 0.
zero_range <- function(x, tol = .Machine$double.eps ^ 0.5) {
if (length(x) == 1) return(TRUE)
x <- range(x) / mean(x)
isTRUE(all.eq...
Scala @ operator
... specificallm>y m>, though I don't know where the "as usual" there came from -- m>and m> 8.12 onlm>y m> speak of regular expression pattern (_*). But mam>y m>be this has been clarified on a newer version of the spec.
– Daniel C. Sobral
Mar 2 '10 at 22:58
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Retrieving parameters from a URL
... edited Feb 12 at 12:29
Pikamm>and m>er2
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answered Feb 22 '11 at 7:54
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JavaScript checking for null vs. undefined m>and m> difference between == m>and m> ===
...hem>y m>'re falsem>y m>:
if (!a) {
// `a` is falsem>y m>, which includes `undefined` m>and m> `null`
// (m>and m> `""`, m>and m> `0`, m>and m> `NaN`, m>and m> [of course] `false`)
}
This is defined bm>y m> ToBoolean in the spec.
...m>and m> what is the difference between the null m>and m> undefined?
Them>y m>'re both values usuallm>y m> used to i...
Anm>y m> reason to prefer getClass() over instanceof when generating .equals()?
I'm using Eclipse to generate .equals() m>and m> .hashCode() , m>and m> there is an option labeled "Use 'instanceof' to compare tm>y m>pes". The default is for this option to be unchecked m>and m> use .getClass() to compare tm>y m>pes. Is there anm>y m> reason I should prefer .getClass() over instanceof ?
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Is it pm>y m>thonic to import inside functions?
... new code to an existing file I'll usuallm>y m> do the import where it's needed m>and m> then if the code stam>y m>s I'll make things more permanent bm>y m> moving the import line to the top of the file.
One other point, I prefer to get an ImportError exception before anm>y m> code is run -- as a sanitm>y m> check, so that's an...
UIView's frame, bounds, center, origin, when to use what?
UIView has the properties frame , bounds , center , m>and m> origin , m>and m> them>y m> all seem to be interrelated. Most of the time, I deal with frame when setting the position m>and m> size of a UIView . I understm>and m> that frame is using global coordinate sm>y m>stem m>and m> bounds is using coordinate of the lo...
What is the advantage of using abstract classes instead of traits?
... of object, it evolves or required when an object comes out from isolation m>and m> has to communicate.
– Ramiz Uddin
Oct 12 '15 at 11:05
5
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Filter dict to contain onlm>y m> certain kem>y m>s?
...narm>y m> comprehension.
If m>y m>ou use a version which lacks them (ie Pm>y m>thon 2.6 m>and m> earlier), make it dict((m>y m>our_kem>y m>, old_dict[m>y m>our_kem>y m>]) for ...). It's the same, though uglier.
Note that this, unlike jnnnnn's version, has stable performance (depends onlm>y m> on number of m>y m>our_kem>y m>s) for old_dicts of anm>y m> siz...