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Whilst every sane Forth has a separate floating-point stack, it is not strictly required; an ANS Forth system could theoretically keep floating-point numbers on the data stack. As an additional difficulty, you don't know how many cells a floating-point number takes. It is reportedly possible to write words in a way that they work also for a unified stack model, but we do not recommend trying it. Instead, just say that your program has an environmental dependency on a separate floating-point stack.

`floating-stack`

– nenvironment “floating-stack”

`n` is non-zero, showing that Gforth maintains a separate
floating-point stack of depth `n`.

`fdrop`

r –float “f-drop”

`fnip`

r1 r2 – r2gforth “f-nip”

`fdup`

r – r rfloat “f-dupe”

`fover`

r1 r2 – r1 r2 r1float “f-over”

`ftuck`

r1 r2 – r2 r1 r2gforth “f-tuck”

`fswap`

r1 r2 – r2 r1float “f-swap”

`fpick`

f:... u – f:... rgforth “fpick”

Actually the stack effect is ` r0 ... ru u -- r0 ... ru r0 `

.

`frot`

r1 r2 r3 – r2 r3 r1float “f-rote”