Targets and Quarto projects

[petrbouchal]

It would be great if targets could integrate with document/project workflows in the maturing Quarto framework. Quarto seems to have its own way of only rendering documents that are out of date (freeze) but presumably these would not pick up changes in upstream targets.

For projects (an evolution of rmarkdown websites/bookdown projects that I recall were too knotty for targets to handle the project-level rendering), one simple solution that comes to mind would be for {targets} to touch quarto files whose upstream targets have changed. (I wonder if this is something that {targets} could provide as a general-purpose functionality for other uses.) Then it could be left to the user to render the whole project in Quarto using the freeze functionality (assuming that Quarto detects changes using modification time).

Separately, it would be great to have dedicated tar_render-style functions for the Quarto workflow rendering individual files.

[wlandau]

Great set of suggestions! Haven't looked too deeply at Quarto yet, but it is an exciting effort, and I could see a place for tar_render()-like target factory.