Bear with me here! The error message is exactly what we’d expect in this situation. The author literally tried to use the string “107” as an executable name, and bash says ‘I can’t find an executable named “107”’.

It’s impossible to be a good software engineer in 2023 without understanding the basics of shell programming. And the absolute number one thing to understand about bash and related shell languages is that “everything is text”. I know one hears people saying that a lot, but you’ve got to really internalize what it means. bash is just constructing strings of text and doing stuff with it. It barely has any non-string data structures.

Well, no. That string was not literally used there at all: if it was, there would have been a literal 107 in the user's input. There wasn't.

> It’s impossible to be a good software engineer in 2023 without understanding the basics of shell programming

> bash is just constructing strings of text and doing stuff with it

It's a reassuring knowledge in 2023, after 40 years of countless bugs, exploits, vulnerabilities and accidentally rm-ed important files, the paradigm of "just constructing strings of text and (blindly) doing stuff with it" is still ubiquitously used and one can not be a good software engineer without extensive knowledge of it. Bash truly deserves description of "a mistake, carried through to perfection. It is the language of the future for the programming techniques of the past: it creates a new generation of coding bums" much more than APL.

The author did not try to use literally 107 as a command.