This fixes#1668, because the crashing listbox rendering code uses "len(line) >
0" (where line is a ui.Text) to test whether it is non-empty. This test doesn't
work with the ui.Text constructed using "styled ''", which creates a ui.Text
with one empty segment.
The functions from the ui package are guaranteed to never return such ui.Text
instances, so switching the implementation of the styled builtin to functions
from the ui package fixes this.
The elvdocs still use the old format (#elvdoc:fn or #elvdoc:var) for now, but
will be changed to "fn" and "var" forms soon.
Also remove the accidentally committed cmd/mvelvdoc. It has been used to perform
the conversion automatically but is not supposed to be committed.
I was surprised to see so many legacy lambda syntax examples in the
documentation. This replaces all of them with the new syntax -- excluding
the handful of cases meant to explicitly verify the legacy form is still
valid. This also adds a link to the issue in the release notes which
documents the change in syntax.
Related #664
I noticed that most places in the documentation that emit a "note"
about Elvish behavior use `**Note**:`. There were two places that use
all uppercase. Make those consistent with the other uses. Also clarify
the note associated with the `not` builtin.
Document that an unqouted `#` character has special meaning to the Elvish
parser in the context of passing `#RGB` values to the `styled` command.
Also document the `fg-` color name prefix.
