unixhost> # case 1 without eval
unixhost> perl -ew '$foo = { bar => () };'
Name "main::foo" used only once: possible typo at -e line 2.
Odd number of elements in hash assignment at -e line 2.
unixhost>
unixhost> # case 2 - now "protect it" with eval ...
unixhost> perl -ew 'eval "$foo = { bar => () };";'
unixhost>
unixhost> # nothing!