Using Erlang to read a whole text file into a variable, do text replacement and write modified file to new directory
erlang, file, full-text-search, variable-assignment
Solution
For the first question, `file:read_file/1` returns a tuple of `{Status, Result}`, so the assignment should rather be like:
{ok, File} = file:read_file("pbd4e53e0.html").
Second, `File` will be a binary, not a string, so you need to convert it to a string first:
Content = unicode:characters_to_list(File).
(You can provide the encoding argument as well)
Then `string:len(Content)` will work as expected.
As for the replacements part, it's generally a very bad idea to use regex with HTML, but from the API point of view looks ok.
Problem
Problem: want to read content of a file (size less than 1MB) into a Erlang variable, do some text replacement and write modified contents to a new file. I am new to Erlang and want to use simple code with no error handling (use it from Erlang shell). I have tried: ``` File = file:read_file("pbd4e53e0.html"). ``` But when using ``` string:len(File). ``` I get exception error: bad argument in function length/1 called as length({ok,<<">}) in call from string:len/1 (string.erl, line 66). Next step is to do replacement: ``` re:replace(File, "<a href=\'pa", "<a href=\'../pa/pa", [{return, list}]). ``` Question 1: How should I read the file into an Erlang variable? Question 2: Is the replacement ok?