Nicolas Williams
9a4576e756
This reverts commit e24af3c78e.
While the semantics are desirable, there is no way to implement them
efficiently. The reason is that in order to handle backtracking (empty)
from the state update expression, we have to retain a reference to the
reduction state value in order to restore it upon backtracking.
Retaining a reference to the reduction state kills performance by
causing lots of additional memory allocations and garbage because the
input to the update expression will always have at least two references,
thus no changes to it can be done in-place, and all changes end up being
CoW changes.
Avoiding this is the very reason for the LOADVN instruction (leaving
`null` in the variable loaded from).
Documentation
The jq website, manpages and some of the tests are generated from this
directory. The directory holds a Bonsai
website, and the manual is a YAML file in content/3.manual.
To build the documentation (including building the jq manpage), you'll need a working Ruby setup. The easiest way to get one is to install RVM and Ruby 1.9.3 like so:
\curl -L https://get.rvm.io | bash -s stable --ruby=1.9.3
After that finishes installing, you'll need to make sure RVM is on
your path by doing source $HOME/.rvm/scripts/rvm, or just opening a
new shell. See https://rvm.io for more info on RVM.
Once RVM is installed, you can install all the dependencies for jq's
documentation build by running this from the docs directory:
bundle install
When bundle manages to install the dependencies, rerun ./configure
in the jq root directory and then the Makefile will be able to
generate the jq manpage.