README.md

In arendsee/ratr: An R wrapper for rat

ratr

An R package wrapper for Rat

Status

This package is highly unstable. It is a wrapper for rat, a language that is not fully specified and whose compiler only has a subset of the full functionallity implemented. rat compiles rat language into a intermediate instructions, which are then translated into R code by the R backend. Language requirements are driven by pied, a workflow package.

A quick example:

rat code:

(A --> B) (C --> D) --> E

Where A, B, C, D, and E are function classes.

The rat compiler frontened translates this into an intermediate language:

emit  A    A_1
emit  B    B_2
link  B_2  A_1
emit  C    C_3
emit  D    D_4
link  D_4  C_3
emit  E    E_5
link  E_5  B_2  D_4

Where A_1 is an instance of A.

The rat R backend then translates this into the following R code

A_1 <- A()
B_2 <- B()
B_2 <- link(B_2, A_1)
C_3 <- C()
D_4 <- D()
D_4 <- link(D_4, C_3)
E_5 <- E()
E_5 <- link(E_5, B_2, C_4)

This code can then be evaluated in R. The function class A, B, C, D, and E must be in scope, along with the link function.

This example will be out-of-date by early this afternoon, but it shows the basic approach.

ratr passes the rat code to the rat compiler and receives the R code as a character vector. I may package the code a bit, perhaps add handling for plotting the function graph. Maybe I'll add some checking. I cannot, however, evaluate the code within ratr, since the function classes will be defined in the code that calls ratr. Therefore, the onus of implementing link and the function classes lies with the user.

arendsee/ratr documentation built on May 10, 2019, 1:25 p.m.