The logger emits log events in a format that is
consistent with logga:
newline-delimited JSON streamed to stderr, with the tag,
a message string and an integer level:
logger(tag)
| tag | The tag for all log events emitted |
|---|
0: error
1: warning
2: info
3: debug
This consistency allows for log events to be merged with those from other Stencila executors, e.g. Encoda, Pyla for easier cross application and cross language tracing and debugging.