The problem is more the spaces than the quotes. For example, in bash you sometimes see something like this:

if [[ x"$a" == x ]]; then
    # $a was empty, so do something
fi
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You can just put characters right beside the quotes like that. So focus more on the spaces than the quotes. The quotes you always see around a command are just there to protect the spaces! (plus single quotes obviously prevent variables from interpolating)

perl -le print\ \''hello world!\n'\'
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(That's like perl -le 'print 'hello world!\n'' except it works. :) The inner pair single-quotes are there just to keep the space and \n from being interpolated by the shell.)