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[Contents][Index] Dynamic Environment Instructions  Guile’s
virtual machine has low-level support for dynamic-wind, dynamic
binding, and composable prompts and aborts.  Instruction: wind
Pop an unwind thunk and a wind thunk from the stack, in that
order, and push them onto the “dynamic stack”. The unwind thunk
will be called on nonlocal exits, and the wind thunk on
reentries. Used to implement dynamic-wind.  Note that neither
thunk is actually called; the compiler should emit calls to wind
and unwind for the normal dynamic-wind control flow. See Dynamic
Wind.  Instruction: unwind  Pop off the top entry from the
“dynamic stack”, for example, a wind/unwind thunk pair. unwind
instructions should be properly paired with their winding
instructions, like wind.  Instruction: wind-fluids n  Pop off n
values and n fluids from the stack, in that order. Set the
fluids to the values by creating a with-fluids object and
pushing that object on the dynamic stack