packagename.SomeFunction should match
github.com/someuser/packagename.SomeFunction since the former is
the familiar syntax.
To disambiguate between io.SomeFunction and
github.com/someuser/somepackage/io.SomeFunction specify one extra
slash at the start of the location specifier: /io.SomeFunction.
Fixes Issue #296
Without arguments, `list` displays source around the current context. A
linespec argument can be taken to display source around that location.
Fixes#58
Breakpoints, tracepoints, etc.. take a location spec as input. This
patch improves the expressiveness of that API. It allows:
* Breakpoint at line
* Breakpoint at function (handling package / receiver smoothing)
* Breakpoint at address
* Breakpoint at file:line
* Setting breakpoint based off regexp