failing breaks

whiel out driving yesterday i had to break sharpley and nothing happend my foot went straight to the floor. i maneged not to hit anything thow..after that they went back to normal. there are no fluid leaks whatsoever.has any body els had this problem befor? i am presuming its the abs pump? your imput would be greatfull. {range rover 1998 dt}.

There's a thread on rangerovers.net on brake failure, apparently there is a plastic piston that can fail suddenly, however I don't think the brakes can come back after that.
What can happen though is the failure of one circuit. I had a brake pad fail on a classic which led to a similar situation where the pedal goes to the floor but comes back on pumping. Another possibility is the failure of a piston seal which can lead to loss of pressure on one circuit.
Either way you shouldn't be driving around, you need to get it checked as if you have a circuit failure its only a matter of time before you run out of fluid and lose all braking on the second circuit.

sounds like a master cyl seal has died