stack.ops - Stack Ops
Operations that manipulate Parrot's register and user stacks.
These operations affect entire sets of registers.
- Save all of the registers onto the register stack.
- Restore all the registers from the register stack.
These operations affect individual registers.
- entrytype(out INT,
- Gets the type of entry $2 of the user stack and puts it in $1.
- depth(out INT)
- Puts the depth of the user stack in $1.
- lookback(out INT,
- lookback(out STR,
- lookback(out NUM,
- lookback(out PMC,
- Finds the entry in the user stack at offset $2 from the top and put it in register $1.
Positive numbers count down from the top of the stack,
negative numbers count up from the bottom.
(0 is the topmost entry,
-1 is the bottom-most)
- save(in INT)
- save(in NUM)
- save(in STR)
- save(in PMC)
- Save register or constant $1 onto the user stack.
- savec(in STR)
- Save a clone of register or constant $1 onto the user stack.
- restore(out INT)
- restore(out NUM)
- restore(out PMC)
- restore(out STR)
- Restore register $1 from the user stack.
- rotate_up(in INT)
- Rotate the top $1 entries in the user stack by one.
If $1 is positive,
then the stack rotates upwards: the ($1)th entry becomes the ($1-1)th entry and so on,
all the way up to the top of the stack,
while the entry formerly at the top of the stack becomes the new ($1)th entry.
If $1 is negative,
the stack rotates downwards: the top entry becomes the second entry,
the second becomes the third etc.,
while the former ($1)th entry becomes the new top entry.
Copyright (C) 2001-2004 The Perl Foundation.
All rights reserved.
This program is free software.
It is subject to the same license as the Parrot interpreter itself.