pushregs()

pushregs(<number>)
pushregs(<changes>)

Saves registers and puts them back later in the same command. It returns nothing.

A positive <number> of 1 or more saves every register that is set. 0, or a fraction below 1, puts every saved register back, then empties the saved copies, so a second 0 empties those registers. A negative number is read as <changes>.
<changes> is a space-separated list. +<register> saves one register and -<register> puts it back. A register is named by one letter or digit.

For code that should not change the caller’s registers at all, localize() is simpler. pushregs() comes from RhostMUSH.

> think [setq(0,one)][pushregs(1)][setq(0,two)]%q0 [pushregs(0)]%q0
two one
> think [setq(a,x)][pushregs(+a)][setq(a,y)][pushregs(-a)]%qa
x

Output: register 0 back to one; register a back to x.

::: seealso