R String Interpretation: why is "\ 040" interpreted as "" and what other potential errors can I encounter in the interpretation of strings?

Question

I helped someone regex today get some information from a pdf file that we read as a txt file. Unfortunately, the readPDF function of tm packages did not work correctly at that time, although after a few changes we were able to make it work normally. While we were reviewing some of the fluff from the .txt file, we discovered what was surprising to most of us, namely that the string "\ 040" is interpreted as a space ".".

> x <- "\040"    
> x    
> [1] " "

This does not happen for other similar character strings (ie "\ n" or "\ t") that you can expect to happen.

> y <- "\n"   
> y    
> [1] "\n"    
> z <- "\t"    
> z    
>[1] "\t"

? - R?

EDIT:

, "\ xxx", x - , . ?

Answer 1

: http://stat.ethz.ch/R-manual/R-devel/library/base/html/Quotes.html

escape- . , , .

...

\nnn (1, 2 3 )

ASCII, , . , 040 - .

:

> '\110\145\154\154\157\040\127\157\162\154\144\041'
[1] "Hello World!"