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'str' object does not support item assignment in Python
I would like to read some characters from a string and put it into other string (Like we do in C).
7 Answers
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Is a Python dictionary an example of a hash table?
One of the basic data structures in Python is the dictionary, which allows one to record "keys" for looking up "values" of any type. Is this implemented internally as a hash table? If not, what is it?
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In Gradle, is there a better way to get Environment Variables?
In several Tasks, I reference jars in my home folder.
3 Answers
3
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Ruby on Rails: How do I add a not null constraint to an existing column using a migration?
In my Rails (3.2) app, I have a bunch of tables in my database but I forgot to add a few not null constraints. I've googled around but I can't find how to write a migration which adds not null to an existing column.
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Custom ImageView with drop shadow
Okay, I've been reading and searching around, and am now banging my head against the wall trying to figure this out. Here's what I have so far:
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How to create a loop in bash that is waiting for a webserver to respond?
How to create a loop in bash that is waiting for a webserver to respond?
6 Answers
6
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C/C++ NaN constant (literal)?
Is this possible to assign a NaN to a double or float in C/C++? Like in JavaScript you do: a = NaN . So later you can check if the variable is a number or no.
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Python `if x is not None` or `if not x is None`?
I've always thought of the if not x is None version to be more clear, but Google's style guide and PEP-8 both use if x is not None . Is there any minor performance difference (I'm assuming not), and is there any case where one really doesn't fit (making the other a clear winner for my convent...
Is it safe to remove selected keys from map within a range loop?
How can one remove selected keys from a map?
Is it safe to combine delete() with range, as in the code below?
4 Answers
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How to fix Array indexOf() in JavaScript for Internet Explorer browsers
If you have worked with JavaScript at any length you are aware that Internet Explorer does not implement the ECMAScript function for Array.prototype.indexOf() [including Internet Explorer 8]. It is not a huge problem, because you can extend the functionality on your page with the following code.
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