This is generally a fine practice: Putting implementations in headers
makes them harder to read and slows compilation. Unfortunately it is
necessary for templates, but we can ameliorate that by putting them in a
separate header. Only files which need to instantiate those templates
will need to include the header with the implementation; the rest can
just include the declaration.
This is now documenting in the contributing guide.
Also, it just happens that these polymorphic serializers are the
protocol agnostic ones. (Worker and serve protocol have the same logic
for these container types.) This means by doing this general template
cleanup, we are also getting a head start on better indicating which
code is protocol-specific and which code is shared between protocols.
While this is not actually a notion in the implementation, it is
explicitly described in the thesis and quite important for understanding
how the store works.
Co-authored-by: John Ericson <git@JohnEricson.me>
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
Introduce what substituters "are" in the configuration option entry.
Remove arbitrary line breaks for easier editing in the future.
Link glossary some more.
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
Co-authored-by: John Ericson <git@JohnEricson.me>
packages and configurations are not really a concept in Nix or the Nix language. the idea of transforming files into other files clearly captures what it's all about, and the new phrasing should make the term "derivation" more obvious both in terms of meaning and origin.
Add support to --list-generations
as another way to say
nix-env --profile /nix/var/nix/profiles/per-user/$USER/channels --list-generations
the way we did for nix-channel --rollback [generation id]
The primop `builtins.replaceStrings` currently always strictly evaluates the
replacement strings, however time and space are wasted for their computation
if the corresponding pattern do not occur in the input string. This commit
makes the evaluation of the replacement strings lazy by deferring their
evaluation to when the corresponding pattern are matched and memoize the result
for efficient retrieval on subsequent matches.
The testcases for replaceStrings was updated to check for lazy evaluation
of the replacements. A note was also added in the release notes to
document the behavior change.
it's more likely for readers to find it right there.
this also slightly rewords examples to make them stand out better.
in the long run there probably needs to be a dedicated section on formal syntax, and better highlighting of examples.
e.g. nix-env -e subversion => nix-env --uninstall subversion
The aim is to make the documentation less cryptic for newcomers and the
long options are more self-documenting.
The change was made with the following script:
<https://github.com/aschmolck/convert-short-nix-opts-to-long-ones>
and sanity checked visually.
This gives some more context and should clarify why it works that way.
Also link it from the section on `NIX_USER_CONF_FILES`.
Co-authored-by: John Ericson <git@JohnEricson.me>
`/etc/bash.bashrc` is backed up as `/etc/bash.bashrc.backup-before-nix`,
but since other changes might have been introduced in the meantime we can't
just tell the user to revert.
