Le 31/10/2012 21:33, Chris Nicholson-Sauls a écrit :
Some related actual code from a while back:################################################## ParseTree prune ( ParseTree p ) { p.children = p.children.dup; foreach ( ref child ; p.children ) { child = prune( child ); } switch ( p.ruleName ) { // strip prefix/suffix terminals, then if left with only one child, skip over it case "Args" : case "List" : case "Params" : case "Table" : p.children = p.children[ 1 .. $ - 1 ]; if ( p.children.length == 1 ) { // skip over immediate child (always a "Series") case "QualIdent" : case "Type" : p.children = p.children[ 0 ].children; } break; // skip self if it has exactly one child case "Addition" : case "BoolAnd" : case "BoolOr" : case "Comparison" : case "Conditional" : case "MaybeParens" : case "Multiplication" : case "Postfix" : case "Primary" : case "Unary" : if ( p.children.length == 1 ) { // skip self case "Expression" : case "Field" : case "Ident" : case "Literal" : case "PathElem" : case "Statement" : p = p.children[ 0 ]; } break; default: } return p; } ################################################## Without the loosely defined switch() statement syntax, this would have been a royal pain to piece together. Especially when each block of cases was evolving over time. There is also the trick of doing 'switch(val) with(EnumType) {...}' to bring an enum's members into scope so that cases can be written as 'case Foo:' rather than 'case EnumType.Foo:'. -- Chris Nicholson-Sauls
Wow this is not actually the case presented in y first post, but still very interesting.
