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What is the most efficient string concatenation method in python?
...and.
Finally, the golden rule of optimization: don't optimize unless you know you need to, and measure rather than guessing.
You can measure different methods using the timeit module. That can tell you which is fastest, instead of random strangers on the internet making guesses.
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What is a None value?
...right and F = None resets F to its original state, then it should be there now, and we should see
>>> print(F)
None
like we do after we type F = None and put the sticker on None.
So that's all that's going on. In reality, Python comes with some stickers already attached to objects (b...
How to add to an existing hash in Ruby
...'
# This is then available immediately
hash[:b]
# => "Bee"
# The hash now contains both keys
hash
# => { :a => 'a', :b => 'Bee' }
Ruby on Rails confuses this somewhat by providing HashWithIndifferentAccess where it will convert freely between Symbol and String methods of addressing.
...
Bootstrap dropdown sub menu missing
...Mark Otto..
"Submenus just don't have much of a place on the web right now, especially the mobile web. They will be removed with 3.0" - https://github.com/twbs/bootstrap/pull/6342
But, with a little extra CSS you can get the same functionality.
Bootstrap 4 (navbar submenu on hover)
.navbar-n...
List comprehension rebinds names even after scope of comprehension. Is this right?
...
Also note that now in 2.7, set and dictionary comprehensions (and generators) have private scopes, but list comprehensions still don't. While this makes some sense in that the former were all back-ported from Python 3, it really makes the c...
Storing time-series data, relational or non?
...s to the disk space used.
You can get rid of it. Please.
Elevation
Now that you have removed the impediment, you may not have recognised it, but your table is in Sixth Normal Form. Very high speed, with just one Index on the PK. For understanding, read this answer from the What is Sixth Nor...
Cross-browser testing: All major browsers on ONE machine
...f using Sandboxie to run IE7 and IE8 in the same VM, thanks for the guide! Now I don't have to run three separate VMs just to test in IE6-IE8.
– Phil
Jan 8 '13 at 3:56
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String concatenation: concat() vs “+” operator
...ring cat(String a, String b) {
a += b;
return a;
}
}
Now disassemble with javap -c (included in the Sun JDK). You should see a listing including:
java.lang.String cat(java.lang.String, java.lang.String);
Code:
0: new #2; //class java/lang/StringBuilder
3: dup
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displayname attribute vs display attribute
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Good to know! Was about to implement a custom attribute to load the display value from the .resx file, then happened on this question. Display attribute is the way to go when developing localized applications.
– ...
org.hibernate.MappingException: Could not determine type for: java.util.List, at table: College, for
... @Arthur Ronald F D Garcia: Thanks, it worked great. But, the program is now stopped by new one. object references an unsaved transient instance - save the transient instance before flushing Do you aware of this error. If not just leave it. I am searching.
– user405398
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