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Why do I need 'b' to encode a string with Base64?
...-z, 0-9, +, /* so it can be transmitted over channels that do not preserve all 8-bits of data, such as email.
Hence, it wants a string of 8-bit bytes. You create those in Python 3 with the b'' syntax.
If you remove the b, it becomes a string. A string is a sequence of Unicode characters. base64 ha...
How to define a function in ghci across multiple lines?
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For guards (like your example), you can just put them all on one line and it works (guards do not care about spacing)
let abs n | n >= 0 = n | otherwise = -n
If you wanted to write your function with multiple definitions that pattern match on the arguments, like this:
fac...
Why is debugging better in an IDE? [closed]
...hat an IDE debugger will give you over trace messages in code:
View the call stack at any point in time, giving you a context for your current stack frame.
Step into libraries that you are not able to re-compile for the purposes of adding traces (assuming you have access to the debug symbols)
Chan...
How can I mix LaTeX in with Markdown? [closed]
...s LaTeX processor with the command: pandoc -s -i Hello.md -o Hello.pdf
Finally, there are some open source LaTeX templates like this one: https://github.com/Wandmalfarbe/pandoc-latex-template, that can be used for better formatting.
As always, the reader should dig deeper if he has less trivial use...
Determine if a String is an Integer in Java [duplicate]
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The most naive way would be to iterate over the String and make sure all the elements are valid digits for the given radix. This is about as efficient as it could possibly get, since you must look at each element at least once. I suppose we could micro-optimize it based on the radix, but for a...
techniques for obscuring sensitive strings in C++
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Basically, anyone with access to your program and a debugger can and will find the key in the application if they want to.
But, if you just want to make sure the key doesn't show up when running strings on your binary, you could ...
Python to print out status bar and percentage
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There's a Python module that you can get from PyPI called progressbar that implements such functionality. If you don't mind adding a dependency, it's a good solution. Otherwise, go with one of the other answers.
A simple example of how to use it:
import progressbar
from time...
Observer Design Pattern vs “Listeners”
It seems to me that the Observer design pattern as described in GOF is really the same thing as Listeners found in various toolkits. Is there a difference between the concepts, or are Listeners and Observers really the same thing.
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How to grep and replace
I need to recursively search for a specified string within all files and subdirectories within a directory and replace this string with another string.
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MySQL: Fastest way to count number of rows
...olumn indexes, so it will be the best result. Mysql with MyISAM engine actually stores row count, it doensn't count all rows each time you try to count all rows. (based on primary key's column)
Using PHP to count rows is not very smart, because you have to send data from mysql to php. Why do it whe...