dot-_: Pass first argument as dot to run code in second argument for...

In SciViews/flow: Data Analysis Work Flow and Alternate Pipeline Operator

Pass first argument as dot to run code in second argument for pipe operators that do not natively support dot-replacement scheme (base R pipe operator)

Description

Pass first argument as dot to run code in second argument for pipe operators that do not natively support dot-replacement scheme (base R pipe operator)

Usage

._(x, expr)

Arguments

x	Object to pass to expr as dot (.).
expr	Expression to execute, containing . as a placeholder.

Details

The function has a side-effect to assign x as . and unevaluated expr as .call in the calling environment. Therefore, make sure you do not use . or .call there for something else. In case expr fails in the middle of a series of chained pipes, you can inspect . and .call or possibly rerun a modified version of the instruction that failed on it for easier debugging purpose.

Value

The result from executing expr in the parent environment.

Examples

# The function is really supposed to be use in a pipe instruction
# This example only runs on R >= 4.1
## Not run: 
# lm has data = as second argument, which does not fit well with the pipe |>
# In R 4.1, one should write:
iris |> \(.)(lm(data = ., Sepal.Length ~ Petal.Length + Species))()
# which is not very elegant ! With ._() it is more concise and straighforward
iris |> ._(lm(data = ., Sepal.Length ~ Petal.Length + Species))

## End(Not run)

SciViews/flow documentation built on Sept. 9, 2023, 10:22 a.m.