bash code generation helpers

`lib.bash.catchErrorExec`

Generate bash code which executes a sequence of commands and stores their standard output and return code in cmd_out and cmd_ret variables.

catchErrorExec ["foo" "bar" "baz"]
=>
"set +e;cmd_out=$(foo bar baz 2>&1);cmd_ret=$?;set -e"

catchErrorExec :: [String] -> String

commands : List of commands to be executed

Generate bash code representing program invocation command

command {flags=["foo"];parameters={bar="baz";};program="qux";}
=>
"qux --foo --bar baz"

options :: AttrSet -> String

config : Configuration including flags and parameters and program path

Generate bash code printing a message into standard error stream

echoError "foo bar"
=>
"echo \"foo bar\" >&2"

echoError :: String -> String

message : Message to be printed

Generate bash code which matches a text against a pattern

matchPattern {pattern="a([[:lower:]])c?";text="ab";}
=>
"[p \"ab\" =~ a([[:lower:]])c? ]]"

echoError :: AttrSet -> String

config : Configuration including pattern and text

Generate bash code representing command options

options {flags=["foo"];parameters={bar="baz";};}
=>
"--foo --bar baz"

options :: AttrSet -> String

config : Configuration including flags and parameters