Yeah, but LISP doesn't do currying and I find Scala's support for currying just fine, although the syntax in F# is definitely much nicer.
Also Scala does optimize self-recursive tail-calls and it's pretty easy to work with trampolines. This is a platform limitation btw, as you can't optimize tail-calls without support from the VM. Mono, the open-source .NET implementation, also has problems with optimizing tail-calls (last time I checked) and I don't know about .NET 4.5, but .NET 4 was not optimizing tail-calls on 64-bits Windows. I remember reading a blog post about them fixing it on 64-bits OS in the latest version, but it wasn't the kind of feature you could rely on in the past.
I do have hopes that TCO will make it into the JVM at some point, as there are experiments for it available as part of OpenJDK. Unfortunately the JVM moves at a glacial pace in regards to such features. This is both a blessing and a curse.
I do agree with you. Not having full TCO in a functional language kind of sucks.
and I don't know about .NET 4.5, but .NET 4 was not
optimizing tail-calls on 64-bits Windows.
Actually there's a .tail CLI Opcode in .NET for tail call optimization which is not usually emitted, but the JIT does tail call optimization on 64 bits (not on 32 bits though). You can witness this when you have a C# getter calling itself. On 32 bits, you get a StackOverflowException, on 64 bits it keeps running happily forever. For the specifics: http://blogs.msdn.com/b/clrcodegeneration/archive/2009/05/11...
It's lower level and more limited than full blown FP aware TCO and it may not catch every call pattern, but it's been there for a while.
.NET 4 most certainly does optimize tail-calls, and the 64-bit versions of the CLR contain additional optimizations that the 32-bit versions don't.
In fact, F# is able to target previous version of the CLR (.NET 2.0, 3.0, and 3.5) and I know for a fact that they also support the 'tail.' opcode and perform some TCO (though it handles fewer edge-cases than .NET 4.0 and 4.5).
Also Scala does optimize self-recursive tail-calls and it's pretty easy to work with trampolines. This is a platform limitation btw, as you can't optimize tail-calls without support from the VM. Mono, the open-source .NET implementation, also has problems with optimizing tail-calls (last time I checked) and I don't know about .NET 4.5, but .NET 4 was not optimizing tail-calls on 64-bits Windows. I remember reading a blog post about them fixing it on 64-bits OS in the latest version, but it wasn't the kind of feature you could rely on in the past.
I do have hopes that TCO will make it into the JVM at some point, as there are experiments for it available as part of OpenJDK. Unfortunately the JVM moves at a glacial pace in regards to such features. This is both a blessing and a curse.
I do agree with you. Not having full TCO in a functional language kind of sucks.