Let grammar escape backslashes

[altoiddealer]

Checklist:

• [X ] I have read the Contributing guidelines.

I was trying to develop a grammar string to respond in this format:

(path)"\"(name).safetensors [(hash)]

Here is what I tried...

  grammar_string: |-
    root ::= path? name ".safetensors" " [" hash "]"
    path ::= (folder "\\")*
    folder ::= [a-zA-Z0-9_]+
    name ::= [a-zA-Z0-9_]+
    hash ::= HEX HEX HEX HEX HEX HEX HEX HEX HEX HEX
    HEX ::= [0-9a-fA-F]

error: unknown escape

I then tried this:

path ::= (folder "\")*

error: out of range

Also this:

path ::= (folder "\\\\")*

error: unknown escape

It turns out, the parser was just incapable of escaping backslashes.

Simply adding this condition to the parser code resolves it:

        elif esc == "\\":
            return "\\", src[2:]

[oobabooga]

Thanks for the fix