ochre-lang

Copperbox revision 3176.

I've added initialization expressions to the orchestra syntax - these will allow i-rate variables to be defined and p-fields to be accessed.

P-fields are positional so they are not modular - if a trait tried to use a p-field, it wouldn't know what the p-field pointed to until final composition. Semantically this is wrong - traits should reference named (free-) variables which are closed when the final orchestra is defined, initialization expressions in the orchestra definition allow this.

At the moment initialization expressions have only been added to the front-end, they need adding to the back-end just before final translation to Csound.

Edit - Copperbox revision 3177.

I've added the file InitialExpr.hs that was missing in the last commit, plus some work on the pretty printer.