gsub - Replacing `\` with `\\` in ruby -


i'm trying replace occurrences of \ \\. here first try:

> puts '\\'.gsub('\\', '\\\\') \

i pretty surprised when saw output. after experimenting able wanted this code:

> puts '\\'.gsub('\\', '\\\\\\') \\

why isn't first piece of code working? why need 6 backslashes?

'\\'.gsub('\\', '\\\\')

when substitution occurs, substitution string '\\\\' passed regexp engine, , \\ replaced \. substitution string ends '\\', single backslash.

the idomatic way replace single bachslach double use:

str.gsub(/\\/, '\\\\\\\\\')  # 8 backslashes!

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