lisa-lab/pylearn2 — pull request #538 by jbornschein (2014-01-31 22:59:34+00:00)
Title: Introduce $(VARNAME) as a ${VARNAME} alternative.

$(VARNAME) is resolved much later during parsing such that
some_obj.yaml_src will contain the *un*substituted version of the
YAML source.

This fixes https://github.com/lisa-lab/pylearn2/issues/300