If we're only going to use it in roll_forward/roll_back it's not really worth the trouble.
Now the code inside roll_forward/roll_back reads all at one level of abstraction.
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5T6SHEIT24FYUAZHSC27XXY4ISZIH3O4HID37FARWVZD4EGSVMOQC
TNRO6KLZXIZUFWKCXSWAJHN2CMHS56ATGGULOKMJC2YNCFRJZKLAC
JIWWTY7RDSOBGAOSU7KBOM2SHEM543FOWIM7GEIW3IZWVJ2EDJVAC
OI2U4SQ3DA6X57GWOWCWBHH4VI56QH6PXXFUVPY2ZZZOKE6ZBLFAC
app.update_head(app.Next_version)
app.Head = app.Next_version love.filesystem.write('head', tostring(app.Head))
app.Head = app.Next_version
love.filesystem.write('head', tostring(app.Head))
app.update_head(app.Manifest[PARENT])
app.Head = app.Manifest[PARENT] love.filesystem.write('head', tostring(app.Head))
app.Head = app.Manifest[PARENT]
function app.update_head(head) app.Head = head love.filesystem.write('head', tostring(app.Head))end
function app.update_head(head)
app.Head = head
end