`do` for core

Run a closure, providing it with the pipeline input.

Signature

> do (closure) ...rest --ignore-errors --ignore-shell-errors --ignore-program-errors --capture-errors

closure: the closure to run
...rest: the parameter(s) for the closure
--ignore-errors (-i): ignore errors as the closure runs
--ignore-shell-errors (-s): ignore shell errors as the closure runs
--ignore-program-errors (-p): ignore external program errors as the closure runs
--capture-errors (-c): catch errors as the closure runs, and return them

Run the closure

> do { echo hello }
hello

Run a stored first-class closure

> let text = "I am enclosed"; let hello = {|| echo $text}; do $hello
I am enclosed

Run the closure and ignore both shell and external program errors

> do -i { thisisnotarealcommand }

Run the closure and ignore shell errors

> do -s { thisisnotarealcommand }

Run the closure and ignore external program errors

> do -p { nu -c 'exit 1' }; echo "I'll still run"

Abort the pipeline if a program returns a non-zero exit code

> do -c { nu -c 'exit 1' } | myscarycommand

Run the closure, with a positional parameter

> do {|x| 100 + $x } 77
177

Run the closure, with input

> 77 | do {|x| 100 + $in }