Expression filter block constructor

This block allows filtering rows in a data frame based on R expressions (see dplyr::filter()). Supports multiple conditions with AND/OR logic. Changes are applied after clicking the submit button.

Usage

new_filter_expr_block(exprs = "TRUE", ...)

Arguments

exprs

Reactive expression returning character vector of filter conditions (default: "TRUE" for no filtering)

...

Additional arguments forwarded to blockr.core::new_block()

Value

A block object for expression-based filter operations

See also

blockr.core::new_transform_block()

Examples

# Create a filter block
new_filter_expr_block("mpg > 20")
#> <filter_expr_block<transform_block<block>>>
#> Name: "Filter expr"
#> Data inputs: "data"
#> Initial block state:
#>  $ exprs: chr "mpg > 20"
#> Constructor: blockr.dplyr::new_filter_expr_block()

if (interactive()) {
  # Basic usage with mtcars dataset
  library(blockr.core)
  serve(new_filter_expr_block(), list(data = mtcars))

  # With custom initial condition
  serve(new_filter_expr_block("mpg > 20"), list(data = mtcars))

  # Connected blocks example
  serve(
    new_board(
      blocks = list(
        a = new_dataset_block(),
        b = new_filter_expr_block()
      ),
      links = links(
        from = c("a"),
        to = c("b")
      )
    )
  )
}