PHP has a mechanism that allows you stop the compiler on a given line. This allows you to put non-PHP code after that line without affecting your code. You can put data, JSON, HTML, etc after the __halt_compiler() line and then read it with your script. Here is a simple function that reads the text after your __halt_compiler()

// Borrowed from https://gist.github.com/ziadoz/5286233
function get_halt_str() {
    return file_get_contents(__FILE__, false, null, __COMPILER_HALT_OFFSET__ + 1);
}

See also: Perl version

Perl has a unique feature where if it sees a line that contains __DATA__ the parser will stop there as if the file ended. This allows you put non-perl code after your __DATA__ line: text, json, HTML, etc. Perl will even allow you to read the text after the __DATA__ like it's a normal file handle. This function will read all the text after your __DATA__ block.

sub get_data_str {
    local $/ = undef; # Slurp mode
    return readline(DATA);
}

Note: Perl also recognizes __END__ but that text is not readable.

See also: PHP version