[colm-users] new way of constructing trees

[Adrian Thurston]

Hi,

I'm experimenting with a new way in Colm to make trees. The existing 
construct expression is useful for building trees in a bottom up 
fashion. It is parsed at compile-time to give some static assurance of 
success.

The existing parse expression can be used to parse from a stream source, 
or reparse the text of a tree as a new type. The parsing happens at 
run-time and may fail.

A new third method, the accumulator, can be used to incrementally build 
a tree by parsing little bits at a time. This is useful for building an 
output tree over the course of a top-down, left-right traversal.

See here for a simple example:

http://svn.complang.org/colm/trunk/test/accum.lm
http://svn.complang.org/colm/trunk/test/accum.in

-Adrian