Check that a pipeline can run on a given class — validate

Walks the pipeline and tracks which class each step would receive. Steps declare the classes their generic has methods for, and most steps hand back what they were given; step_metacells_sc() does not, it turns a SingleCells/SingleCellsSubset into a MetaCells. Without this you would only find out about a mismatch when S7 fails to dispatch, i.e. after the expensive steps already ran.

Usage

validate_pipeline(pipeline, class)

Arguments

pipeline: ScPipeline.
class: String. Class of the object the pipeline would start on. One of c("SingleCells", "SingleCellsSubset", "MetaCells").

Value

Invisibly, the class the pipeline would return.

Examples

# the meta cell step changes what the next step would receive
p <- step_hvg_sc() %>>% step_metacells_sc("bootstrapped")
print(validate_pipeline(p, "SingleCells"))
#> [1] "MetaCells"