ECMAScript Version 5 Approved

systembug writes "After 10 years of waiting and some infighting, ECMAScript version 5 is finally out, approved by 19 of the 21 members of the ECMA Technical Committee 39. JSON is in; Intel and IBM dissented. IBM is obviously in disagreement with the decision against IEEE 754r, a floating point format for correct, but slow representation of decimal numbers, despite pleas by Yahoo's Douglas Crockford." (About 754r, Crockford says "It was rejected by ES4 and by ES3.1 — it was one of the few things that we could agree on. We all agreed that the IBM proposal should not go in.")

Comments

Re:I can guess why IBM was pushing for IEEE 754r

[teg]

IEEE 754 has plenty of pitfalls for the unwary but it has one big advantage - it is directly supported by the Intel-compatible hardware that 99+% of desktop users are running. Switching to the IEEE 754r in ECMA Script would have meant a speed hit to the language on the Intel platform until Intel supports it in hardware. This is an area where IBM already has a hardware implementation of IEEE 754r - its available on the POWER6 platform and I believe that the z-Series also has a hardware implementation.

ECMAScript is client side, so I don't think that was the issue. Z-series is server only, and POWER6 is almost all servers - and for POWER workstations, the ability to run javascript a little bit faster has almost zero value. The more likely explanation is that IBM has its roots in business, and puts more importance into correct decimal handling than companies with their roots in other areas where this didn't matter much.

Financial Calculations

[pavon]

When you have strict regulatory rules about how rounding must be done, and your numerical system can't even represent 0.2 exactly, then it is most certainly a concern. There are other solutions, such as using base-10 fixed point calculations rather than floating point, but having decimal floating point is certainly more convenient, and having a hardware implementation is much more efficient.