If non-nil, Emacs ignores ISO-2022 escape sequences during code detection.
When Emacs reads text, it tries to detect how the text is encoded.
This code detection is sensitive to escape sequences. If Emacs sees
a valid ISO-2022 escape sequence, it assumes the text is encoded in one
of the ISO2022 encodings, and decodes text by the corresponding coding
system (e.g. `iso-2022-7bit').
However, there may be a case that you want to read escape sequences in
a file as is. In such a case, you can set this variable to non-nil.
Then the code detection will ignore any escape sequences, and no text is
detected as encoded in some ISO-2022 encoding. The result is that all
escape sequences become visible in a buffer.
The default value is nil, and it is strongly recommended not to change
it. That is because many Emacs Lisp source files that contain
non-ASCII characters are encoded by the coding system `iso-2022-7bit'
in Emacs's distribution, and they won't be decoded correctly on
reading if you suppress escape sequence detection.
The other way to read escape sequences in a file without decoding is
to explicitly specify some coding system that doesn't use ISO-2022 escape sequence (e.g., `latin-1') on reading by C-x RET c.