README.md

In garyfeng/dfat: Data-frame AT: Repurposing the `@` sign for extracting named properties from a list

dfat

An operator @ to extract a named member of a list that is in a list and returns a vector.

note: this library masks the @ or "slotOp" in the base module that is reserved for S4 objects only.

Installation

require(devtools)
devtools::install_github('garyfeng/dfat')

Examples

require(dfat)

testvec <- list(
  list(from=1, to="here", date="1990-12-12"), 
  list(from=2, to="there", via=list("train", "airplane"), date=123.45)
)

key <- "from"

# different ways to invoke `@`
testvec%@%"from"
testvec%@%"to"
testvec@key
testvec@"to"
`@`(testvec, 2)

# the permissive %@@% returns a list instead of coercing into a vector
testvec%@@%"from"
testvec%@@%"to"
`%@@%`(testvec, 2)

See also tests\testthat.R.

garyfeng/dfat documentation built on May 16, 2019, 5:42 p.m.