Styled text is not supposed to "inherit" the current SGR styling context when
written to the terminal. This has always been the intention, but not correctly
implemented. This commit fixes that for both styled segments and styled texts.
Tests are amended to account for the difference in the output.
With context insensitivity correctly implemented, there is now no need for a
"default" color. It is functionally equivalent to a lack of color.
The parsing of SGR still needs to be aware of the codes 39 (default foreground)
and 49 (default background), but these codes are now translated into FgDefault
and BgDefault, which resets the foreground and background color fields.
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
This fixes the *Segment.Concat and RConcat methods to handle the new
number types. It also adds more tests of concatenation with the "Text"
and "Segment" types with number types.
Related #1340
Including the float64 data type in the prompt value stream causes an error.
This causes those values to be implicitly converted to a string as happens
everywhere else in Elvish.
I initially intended to modify the code to do the implicit string coercion
for any type not otherwise explicitly handled by the pkg/ui `Concat`
methods. I decided against that approach because doing so doesn't make
sense for some types that might appear in the value stream; e.g., Elvish
exceptions.
Fixes#1186
