Don’t explicitely give it a constructor, but use aggregate
initialization instead (also prevents having an implicit coertion, which
is probably good here)
* libexpr: fix builtins.split example
The example was previously indicating that multiple whitespaces would be
collapsed into a single captured whitespace. That isn't true and was
likely a mistake when being documented initially.
* Fix segfault on unitilized list when printing value
Since lists are just chunks of memory the individual elements in the
list might be unitilized when a programming error happens within Nix.
In this case the values are null-initialized (at least with Boehm GC)
and we can avoid a nullptr deref when printing them.
I ran into this issue while ensuring that new expression tests would
show the actual value on an assertion failure.
This is unlikely to cause any runtime performance regressions as
printing values is not really in the hot path (unless the repl is the
primary use case).
* Add operator<< for ValueTypes
* Add libexpr tests
This introduces tests for libexpr that evalulate various trivial Nix
language expressions and primop invocations that should be good smoke
tests wheter or not the implementation is behaving as expected.
'nix profile install' will now install all outputs listed in the
package's meta.outputsToInstall attribute, or all outputs if that
attribute doesn't exist. This makes it behave consistently with
nix-env. Fixes#6385.
Furthermore, for consistency, all other 'nix' commands do this as
well. E.g. 'nix build' will build and symlink the outputs in
meta.outputsToInstall, defaulting to all outputs. Previously, it only
built/symlinked the first output. Note that this means that selecting
a specific output using attrpath selection (e.g. 'nix build
nixpkgs#libxml2.dev') no longer works. A subsequent PR will add a way
to specify the desired outputs explicitly.
after #6218 `Symbol` no longer confers a uniqueness invariant on the
string it wraps, it is now possible to create multiple symbols that
compare equal but whose string contents have different addresses. this
guarantee is now only provided by `SymbolIdx`, leaving `Symbol` only as
a string wrapper that knows about the intricacies of how symbols need to
be formatted for output.
this change renames `SymbolIdx` to `Symbol` to restore the previous
semantics of `Symbol` to that name. we also keep the wrapper type and
rename it to `SymbolStr` instead of returning plain strings from lookups
into the symbol table because symbols are formatted for output in many
places. theoretically we do not need `SymbolStr`, only a function that
formats a string for output as a symbol, but having to wrap every symbol
that appears in a message into eg `formatSymbol()` is error-prone and
inconvient.
