| % Generated by roxygen2: do not edit by hand |
| % Please edit documentation in R/expression.R |
| \name{Expression} |
| \alias{Expression} |
| \title{Arrow expressions} |
| \description{ |
| \code{Expression}s are used to define filter logic for passing to a \link{Dataset} |
| \link{Scanner}. |
| |
| \code{Expression$scalar(x)} constructs an \code{Expression} which always evaluates to |
| the provided scalar (length-1) R value. |
| |
| \code{Expression$field_ref(name)} is used to construct an \code{Expression} which |
| evaluates to the named column in the \code{Dataset} against which it is evaluated. |
| |
| \code{Expression$create(function_name, ..., options)} builds a function-call |
| \code{Expression} containing one or more \code{Expression}s. |
| } |
