[Swift-devel] strange behavior evaluating function call as trace arg

[Ben Clifford]

> Looks like most nested invocations are broken, not specifically trace.

They're not 'broken'. If you think they should work, you're thinking far 
too much along the lines of procedure calls evaluating to a value like 
some kind of referentially transparent thing. Procedure calls *must* have 
an lvalue to their l to give them somewhere to put their l. That's been 
the case forever in Swift and in VDL2. Making that not happen is a long 
term goal of mine, but its not in the language now.

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