Add ggplot2 Layers Programmatically — ptr_gg

Evaluate one or more ggplot2 expressions and attach the results as "extras" on the state. Extras are folded into the plot during the next runtime cycle when state$runtime()$ok is TRUE. Eval failures leave the existing extras untouched.

Usage

ptr_gg_extra(state, ...)

Arguments

state: A ptr_state from ptr_init_state().
...: ggplot2 layer expressions (e.g. ptr_gg_extra(state, ggplot2::scale_x_log10(), theme_minimal())). Captured unevaluated and stored as quosures, then evaluated in state$eval_env. Eval errors propagate and leave the existing extras untouched (atomic update).

Value

state, invisibly.

Examples

shiny::isolate({
  state <- ptr_init_state(
    "ggplot(mtcars, aes(x = wt, y = mpg)) + geom_point()"
  )
  state <- ptr_gg_extra(state, ggplot2::theme_minimal())
  ptr_extract_code(state)
})
#> [1] ""