That won't work, for the proposed case: 

Type of arg 1 to main::mygrep must be block or sub {} (not numeric eq 
+(==)) at /tmp/mygrep line 7, near "10)"
Execution of /tmp/mygrep aborted due to compilation errors.

[download]

Perhaps something like this? 

sub mygrep { my $s = "grep $_[0]"; eval $s; }

print for mygrep('$_ % 2 == 0, 0..10');    # :-)

[download]

--
"Language shapes the way we think, and determines what we can think about."
-- B. L. Whorf

In reply to Re^2: make subroutine that takes expression as implicit block as first arg by oko1
in thread make subroutine that takes expression as implicit block as first arg by myuserid7

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