form

The form function converts a value to a string:

form [a block of undefined words]
;== "a block of undefined words"

mold

The mold function converts a value to a string that is usable by REBOL/Red. Strings created with mold can be converted back to values with the load function.

blk: [[11 * 4] (15 - 3.89) "eleven dollars"]
molded-blk: mold blk
;== {[[11 * 4] (15 - 3.89) "eleven dollars"]}
new-blk: load molded-blk
;== [[11 * 4] (15 - 3.89) "eleven dollars"]

The form/mold function does not evaluate the values of a block.