AST formula processing - Githubissues

spgarbet / tangram

Table Grammar package for R

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AST formula processing #27

Closed spgarbet closed 6 years ago

spgarbet commented 7 years ago

Need to fully support R formula parsing. To do this the following steps are requied:

Document using BNF what an R formula is and what it means. Relay this to core R team for inclusion in current documentation.
Expand parser to contain all possibilities of an R formula for table processing.

This will then lead to a greatly expanded number of possible statistical transforms for the Hmisc example.

spgarbet commented 6 years ago

I've been through the core R code and it parses a formula directly as an S-object. Access to the internal AST is none trivial, and sticking with our AST processor provides better control.