mjhjmtu

I'm trying to write a quick bash function that populates a README.md with a $1n followed by underscores the length of $1.

The code I found in other stackexchange questions showed that to print a character <n> times, use

printf '=%.0s' 1..<n>

and indeed, this works (obviously replacing <n> with a number).

To create my README.md, I thought the function would look something like this:

make_readme() 
 echo "$1
$(printf '=%.0s' 1..$#1)" > README.md


make_readme "Some project"

This, however, produces a file with this text:

Some project
=

As far as I can tell, $#1 within the $(...) is being replaced with the empty string. My guess is that command substitutions get their own argument scopes, and since there are no arguments passed to the substitution, $1 is being replaced with nothing.

I did finally finagle a couple workarounds:

make_readme() 
 underline="printf '=%.0s' 1..$#1"
 echo "$1
$(eval "$underline")" > README.md

or

make_readme() 
 echo "$1" > README.md
 printf '=%.0s' 1..$#1 >> README.md

but it seems like there should be a way to do this in one line.