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Rails - Nested includes on Active Records?
...u'd use the array as given in the example in the Rails Guide.
A.includes(bees: [:cees, :dees])
You could continue to nest includes like that (if you actually need to). Say that A is also associated with Z, and that C is associated to E and F.
A.includes( { bees: [ { cees: [:ees, :effs] }, :dees]...
Checkout subdirectories in Git?
...
Sparse checkouts are now in Git 1.7.
Also see the question “Is it possible to do a sparse checkout without checking out the whole repository first?”.
Note that sparse checkouts still require you to download the whole repository, even though some of the files Git ...
Overloading Macro on Number of Arguments
... @Uroc327 Adding a 0-argument macro to the list is possible, see my answer.
– augurar
Jan 27 '14 at 0:59
7
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How to view hierarchical package structure in Eclipse package explorer
OK here's what I would like: in the Eclipse package explorer, I see the following: (dot represents a clickable arrow that I can use to expand the folder)
...
Dynamically Changing log4j log level
...og4j will automatically refresh the log levels according to your changes. See the documentation of org.apache.log4j.xml.DOMConfigurator.configureAndWatch(String,long) for details. The default wait time between checks is 60 seconds. These changes would be persistent, since you directly change the con...
Are Javascript arrays sparse?
...uctor with an explicit length argument and hope you'll actually get one.
See this answer for a more detailed description by olliej.
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How can a JACC provider use the Principal-to-role mapping facilities of the server it's deployed on?
...es no assume all containers do, and so it delegates the responsibility of keeping those mappings to the JACC provider implementation. From the docs (see: PolicyConfiguration.addToRole method):
It is the job of the Policy provider to ensure that all the
permissions added to a role are granted t...
Regular expression for floating point numbers
...umber is
[+-]?([0-9]*[.])?[0-9]+
This will match:
123
123.456
.456
See a working example
If you also want to match 123. (a period with no decimal part), then you'll need a slightly longer expression:
[+-]?([0-9]+([.][0-9]*)?|[.][0-9]+)
See pkeller's answer for a fuller explanation of this...
.war vs .ear file
What is the difference between a .war and .ear file?
9 Answers
9
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Checking if a string can be converted to float in Python
...
I would just use..
try:
float(element)
except ValueError:
print "Not a float"
..it's simple, and it works
Another option would be a regular expression:
import re
if re.match(r'^-?\d+(?:\.\d+)?$', element) is None:
print "Not float"
...