1.4 KiB
stxparse-info
The module stxparse-info/parse
is a patched version of syntax/parse
which
tracks which syntax pattern variables are bound. This allows some libraries to
change the way syntax pattern variables work.
For example, phc-graph/subtemplate
automatically derives temporary
identifiers when a template contains yᵢ …
, and xᵢ
is a pattern
variable. To know from which varᵢ
the yᵢ …
identifiers must be derived,
phc-graph/subtemplate
needs to know which syntax pattern variables are
within scope.
To use this package, simply require stxparse-info/pares
instead of
syntax/parse
Additionally, it is possible to use the for-syntax function
(current-pvars)
from stxparse-info/current-pvars
to access the list of
currently-bound pattern variables, and the macro (with-pvars (pvar ...) . body)
can be used to add new pattern variables to the list.