Is there a way where I can unshift a string to <STDIN>? like: 
# old STDIN: 1 2 3
while (<STDIN>) {
   if (some condition) unshift "hi test test" to STDIN
   # new STDIN hi test test 1 2 3 
}

[download]
if some condition is met, the string "hi test test" will be unshifted onto STDIN. I'm using this to program 'functions' into my forth interpreter (written in perl of course).

In reply to Manipulating STDIN by ChwanRen

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