User friendly delimited continuations. While this was doable with
signals before, this does not require C and will play nicely with
existing error handling, defers, and with statements.
These additions, along with the change that user signals 0-4 cannot
be resumed, allow delimited continuation semantics, while repsecting
existing forms like `defer`, `with`, `with-vars`, etc.
This should help when redefining certain forms. Will also
not do functional arity checking against nil forms, as that
is the default value when a def doesn't evaluate.
Required a few changes to APIs, namely janet_root_fiber()
to get topmost fiber that is active in the current scheduler.
This is distinct from janet_current_fiber(), which gets the bottom
most fiber in the fiber stack - it might have a parent, and so cannot
be reliably resumed.
This is the kind of situation that makes symmetric coroutines more
attractive.
These functions interact with Janet's dynamically scoped
IO functions in a manner that is more useful the file/flush.
We can still redirect to a buffer without changing our code.
This way we can support fewer build configurations. Also, remove
all undefined behavior due to use of memcpy with NULL pointers. GCC
was exploiting this to remove NULL checks in some builds.
Also add a few ctrl sequences from readline, and
ignore unknown ctrl sequences.
Address #264
Adds Ctrl-n, Ctrl-p, and Ctrl-w
Ignores unknown ctrl sequences
No alt-* sequences yet.
This changes the implementation of the `next` function which
is now used to implement each. This let's us iterate over
more types, not just tables and structs.
This unifies equality and comparison checking. Before, we had
separate functions and vm opcodes for comparing general values vs.
for comparing numbers, where the numberic functions were polymorphic and
had special cases for handling NaNs. By unfiying them, abstract types
can now better integrate with other number types and behave as keys.
For now, the old functions are aliased but will eventually be removed.
This adds several common patterns, which are defined in
boot.janet. This essentially gives more primitive patterns
to work with out of the box.
Fix build when JANET_REDUCED_OS is defined.
True top level unquote currently requires basically double compilation
as it currently stands. Also, implementing such double compilation
looses all source mapping information. This is a compromise
implementation that makes it clear that this works differently than
a true top-level unquote.
Rather than messing with janet_core_dictionary, we
instead cache the core enevironment, and pull out the
needed tables from there. This is more flexible, more correct, and
also exposes janet_resolve_core, which can be easily used from the C
API.
doc macro can take no arguments and print out
all bindings. Fix an issues with the vm skipping
over a breakpoint in some situations.
Add examples/debugger.janet for proof of concept
debugger.
The new RNG wraps up state for random number generation, so
one can have many rngs and even marshal and unmarshal them.
Adds math/rng, math/rng-uniform, and math/rng-int.
Also introduce `in` and change semantics for
indexing out of range. This commit enforces stricter
invariants on keys when indexing via a function call
on the data structure, or the new `in` function.
The `get` function is now more lax about keys, and will
not throw an error when a bad key is used for a data structure, instead
returning the default value.
This helps for temporarily setting vars in a safe
manner that is guaranteed not to leave vars in a bad state
(assuming that a fiber does not emit debug or use signal and
is never resumed).
This makes it easier to get the CLI functionality when
embedding Janet, although the main reason is the init script
is now pre-compiled to bytecode when generating the boot image.
Flychecking will now work correctly with arity checking, and
will better handle imports. Well structured modules should interact
cleanly with the flychecker in a mostly safe manner, but maliciously
crafted modules can execute arbitrary code. As such, the flychecker is
not a good way to validate completely untrusted modules.
We also extend run-context with an :evaluator option to replace
:compile-only. This is more flexible and allows users to create their
own flychecker like functionality.
This allows some more optimizations when printing to
buffers or when output is disabled. It also makes printf
more consistent with print and prin (Same with eprintf).
The print family of functions now writes output
to an optional buffer instead of a file bound to :out.
This means output can be more easily captured an redirected.
This should be friendlier to most users. It does, however, mean
we lose range information. However, range information could be
recovered by re-parsing, as janet's grammar is simple enough to do this.
