Format contents into a textual representation

These generic functions can be use to convert Turn contents or Content objects into textual representations.

contents_text() is the most minimal and only includes ContentText objects in the output.
contents_markdown() returns the text content (which it assumes to be markdown and does not convert it) plus markdown representations of images and other content types.
contents_html() returns the text content, converted from markdown to HTML with commonmark::markdown_html(), plus HTML representations of images and other content types.

These content types will continue to grow and change as ellmer evolves to support more providers and as providers add more content types.

contents_text(content, ...)

contents_html(content, ...)

contents_markdown(content, ...)

Arguments

content: The Turn or Content object to be converted into text. contents_markdown() also accepts Chat instances to turn the entire conversation history into markdown text.
...: Additional arguments passed to methods.

Value

A string of text, markdown or HTML.

Examples

turns <- list(
  Turn("user", contents = list(
    ContentText("What's this image?"),
    content_image_url("https://placehold.co/200x200")
  )),
  Turn("assistant", "It's a placeholder image.")
)

lapply(turns, contents_text)
#> [[1]]
#> [1] "What's this image?"
#> 
#> [[2]]
#> [1] "It's a placeholder image."
#> 
lapply(turns, contents_markdown)
#> [[1]]
#> [1] "What's this image?\n\n![](https://placehold.co/200x200)"
#> 
#> [[2]]
#> [1] "It's a placeholder image."
#> 
if (rlang::is_installed("commonmark")) {
  contents_html(turns[[1]])
}
#> [1] "<p>What's this image?</p>\n\n<img src=\"https://placehold.co/200x200\">"