3.7 KiB
%ford
%ford is our typed and marked computation engine.
A variety of different services are provided by %ford, but they mostly
involve compiling hook files, slapping/slammming code with marked data,
and converting data between marks, including validating data to a mark.
Throughout every computation, %ford keeps track of which resources are
dependencies so that the client may be aware when one or more
dependencies are updated.
%ford neither accepts unix events nor produces effects. It exists
entirely for the benefit of applications and other vanes, in particular
%gall. %eyre exposes the functional publishing aspects of %ford
while %gall uses %ford to control the execution of applications.
%clay is intended to use %ford to managed marked data, but this is
not yet reality.
Cards
%ford accepts just one card, %exec. This is misleading, however,
since there are fourteen different silks that may be used with it. In
every case, the expected response to a %exec card is a %made gift
with either an error or the produced result along with its set of
dependencies.
Silks may autocons, so that the product of a cell of silks is a cell of the product of the two silks.
%bake
Tries to functionally produce the file at a given beam with the given mark and heel. It fails if there is no way to translate at this level.
%boil
Functionally produces the file at a given beam with the given mark and
heel. If there is no way to translate at this beam, we pop levels off
the stack and attempt to bake there until we find a level we can bake.
This should almost always be called instead of %bake.
%call
Slams the result of one silk against the result of another.
%cast
Translates the given silk to the given mark, if possible. This is one of the critical and fundamental operations of ford.
%diff
Diffs the two given silks (which must be of the same mark), producing a
cage of the mark specified in ++mark in ++grad for the mark of the
two silks.
%done
Produces exactly its input. This is rarely used on its own, but many silks are recursively defined in terms of other silks, so we often need a silk that simply produces its input. A monadic return, if you will.
%dude
Computes the given silk with the given tank as part of the stack trace if there is an error.
%dune
Produces an error if the cage is empty. Otherwise, it produces the value in the unit.
%mute
Takes a silk and a list of changes to make to the silk. At each wing in the list we put the value of the associated silk.
%pact
Applies the second silk as a patch to the first silk. The second silk
must be of the mark specified in ++mark in ++grad for the mark of
the first silk.
%plan
Performs a structured assembly directly. This is not generally directly useful because several other silks perform supersets of this functionality. We don't usually have naked hoods outside ford.
%reef
Produces a core containing the entirety of zuse and hoon, suitable for
running arbitrary code against. The mark is %noun.
%ride
Slaps a twig against a subject silk. The mark of the result is %noun.
%vale
Validates untyped data from a ship against a given mark. This is an extremely useful function.