You could dump the data to a string and then escape the newliens in it with a regular expression. Then, the other side could undo the escaping and then parse with yaml.

For example, escape newlines with something like this (untested):

s/\x1f/\x1f_/g; s/\n/\x1fj/g;
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and undo it with

s/\x1fj/\n/g; s/\x1f_/\x1f/g;
[download]