Better example/support for reading lines from a file about loop HOT 6 CLOSED

What weird behaviour are you seeing? Empty lines?
If so, try:
cargo run 'echo $ITEM' --for "`cat README.md`"

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Yes, I was seeing empty lines, but that fixed it. Why does the type of quote matter?

from loop.

That's because of your shell, probably bash.

Try echo "$TERM" and then echo '$TERM'

You'll see that the first time it outputs the value of $TERM, but the second time it outputs a literal $TERM. Double quotes allow variable substitution, single quotes prohibit.

Specifically, when you execute cargo run, the $ITEM is replaced with the value of $ITEM in the parent shell of cargo, aka, the current shell you're in, instead of the shell that loop spins up. $ITEM is most likely empty there.

The same goes for the value of `cat README.md`. This last one doesn't cause a problem though, since both outside loop and inside loop, `cat README.md` would have the same output.

Does that make sense?

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For more info, see for instance http://wiki.bash-hackers.org/syntax/quoting

mind you, this also goes with other advanced shell like ksh.

from loop.

Ha! Okay, thanks for explaining! I learned something new today.

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Looks like this can be closed?

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