VegaPlot

Load a spec from an explicit absolute path on the machine doing the compiling.

Load a spec at a path relative to the discovered project root.

The root is the first ancestor of the calling source file holding a build marker (build.mill, build.sbt, .git, ...).

In a notebook or REPL there is no source file on disk to search upwards from, so the root is discovered from the working directory instead and a compile time warning says so. Declare an anchor with -Xmacro-settings:dedav4s.root=/path/to/dir or System.setProperty("dedav4s.root", "/path/to/dir") to override that - a declared anchor is taken as the root as given.

val scatter = VegaPlot.projectRoot("core/resources/scatter.vl.json")

Load a spec at a path relative to the source file this is called from.

The path is anchored to the calling source file rather than to the compiler's working directory, so it resolves the same way no matter where the build was invoked from.

In a notebook or REPL there is no source file on disk, so the path resolves against the working directory instead and a compile time warning says so. Declare an anchor with -Xmacro-settings:dedav4s.root=/path/to/dir or System.setProperty("dedav4s.root", "/path/to/dir") to override that.

val scatter = VegaPlot.relativeToSource("specs/scatter.vl.json")