bwanab
How to read a file of numeric data as a list of integers?
When you read a file with File.read, you get a large binary. I’m reading a file of numeric data that I would like to have in a list of integers, but I haven’t found any straightforward way to do it. I suspect I’m missing something pretty basic.
I.e. instead of
<<77, 84, 104, 100, 0, 0, 0, 6, 0, 1, 0, 10, 0, 192, 77, 84>>
I want:
[77, 84, 104, 100, 0, 0, 0, 6, 0, 1, 0, 10, 0, 192, 77, 84]
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wojtekmach
I was curious how to read file contents as charlist and I found:
{:ok, pid} = File.open("mix.exs", [:charlist])
IO.inspect IO.read(pid, :all)
# Outputs: {:ok, 'defmodule ...'}
File.close(pid)
kip
String.length/1 counts the number of graphemes, not code points. So definitely not the right tool for the job you are tackling.
I was surprised to see that \r\n is considered a grapheme cluster but it is according to the Unicode standard.
mpope
Why not just keep it as a binary 
if the binary is large, it is allocated to a shared heap and can possibly be more memory efficient. https://medium.com/@mentels/a-short-guide-to-refc-binaries-f13f9029f6e2
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