3. You can't (easily) have any space in front of the tag.

If you want to indent the text in the here document, you can do this:

    # all in one
    ($VAR = <<HERE_TARGET) =~ s/^\s+//gm;
        your text
        goes here
    HERE_TARGET
But the HERE_TARGET must still be flush against the margin. If you want that indented also, you'll have to quote in the indentation.

    ($quote = <<'    FINIS') =~ s/^\s+//gm;
            ...we will have peace, when you and all your works have
            perished--and the works of your dark master to whom you
            would deliver us. You are a liar, Saruman, and a corrupter
            of men's hearts.  --Theoden in /usr/src/perl/taint.c
        FINIS
    $quote =~ s/\s+--/\n--/;
A nice general-purpose fixer-upper function for indented here documents follows. It expects to be called with a here document as its argument. It looks to see whether each line begins with a common substring, and if so, strips that substring off. Otherwise, it takes the amount of leading whitespace found on the first line and removes that much off each subsequent line.

    sub fix {
        local $_ = shift;
        my ($white, $leader);  # common whitespace and common leading string
        if (/^\s*(?:([^\w\s]+)(\s*).*\n)(?:\s*\1\2?.*\n)+$/) {
            ($white, $leader) = ($2, quotemeta($1));
        } else {
            ($white, $leader) = (/^(\s+)/, '');
        }
        s/^\s*?$leader(?:$white)?//gm;
        return $_;
    }
This works with leading special strings, dynamically determined:

    $remember_the_main = fix<<'    MAIN_INTERPRETER_LOOP';
	@@@ int
	@@@ runops() {
	@@@     SAVEI32(runlevel);
	@@@     runlevel++;
	@@@     while ( op = (*op->op_ppaddr)() );
	@@@     TAINT_NOT;
	@@@     return 0;
	@@@ }
    MAIN_INTERPRETER_LOOP
Or with a fixed amount of leading whitespace, with remaining indentation correctly preserved:

    $poem = fix<<EVER_ON_AND_ON;
       Now far ahead the Road has gone,
	  And I must follow, if I can,
       Pursuing it with eager feet,
	  Until it joins some larger way
       Where many paths and errands meet.
	  And whither then? I cannot say.
		--Bilbo in /usr/src/perl/pp_ctl.c
    EVER_ON_AND_ON

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