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Set a persistent environment variable from cmd.exe
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Use the SETX command (note the 'x' suffix) to set variables that persist after the cmd window has been closed.
For example, to set an env var "foo" with value of "bar":
setx foo bar
Though it's worth reading the 'notes' that are displayed...
What does -D_XOPEN_SOURCE do/mean?
...nclude definitions for some extra functions that are defined in the X/Open and POSIX standards.
This will give you some extra functionality that exists on most recent UNIX/BSD/Linux systems, but probably doesn't exist on other systems such as Windows.
The numbers refer to different versions of the...
What does a double * (splat) operator do
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Ruby 2.0 introduced keyword arguments, and ** acts like *, but for keyword arguments. It returns a Hash with key / value pairs.
For this code:
def foo(a, *b, **c)
[a, b, c]
end
Here's a demo:
> foo 10
=> [10, [], {}]
> foo 10, 20, 30
=> [10, [20...
How do I Geocode 20 addresses without receiving an OVER_QUERY_LIMIT response?
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No, there is not really any other way : if you have many locations and want to display them on a map, the best solution is to :
fetch the latitude+longitude, using the geocoder, when a location is created
store those in your database, alongside the address
and use those stored latitude+lon...
Remove all values within one list from another list? [duplicate]
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What if I've a list [1,2,2,2,3,4] and a sublist [2,3], then the result should be [1,2,2,4], is there a Pythonic way to do that?
– user
Mar 2 '14 at 5:20
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How do I encode/decode HTML entities in Ruby?
... Yup, the HTMLEntities gem deals with cases such as å and — which CGI.unescapeHTML does not.
– thomax
Dec 1 '14 at 8:14
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In pure functional languages, is there an algorithm to get the inverse function?
...n algorithm to get the inverse of a function, (edit) when it is bijective? And is there a specific way to program your function so it is?
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Rails: how do I validate that something is a boolean?
...ield (the field would not be valid for a false value). But in both Rails 3 and 4, having validates :field, inclusion: [true, false] would test for inclusion in a list of values, with the side-effect to test for the field's presence (unless one of those values is nil of course).
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Troubleshooting “The use statement with non-compound name … has no effect”
...g namespace; it allows you to define an alias, not to "import" a namespace and thus henceforth omit the namespace qualifier altogether.
So, you could do:
use Blog\Article as BA;
... to shorten it, but you cannot get rid of it entirely.
Consequently, use Blog is useless, but I believe you coul...
What does ||= (or-equals) mean in Ruby?
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This question has been discussed so often on the Ruby mailing-lists and Ruby blogs that there are now even threads on the Ruby mailing-list whose only purpose is to collect links to all the other threads on the Ruby mailing-list that discuss this issue.
Here's one: The definitive list of ||= ...