For to and thru, we need to restore eveytime through the loop since rules need
run with the right captures on the stack, especially if they have any
sort of backrefs.
This is the beginning of a system for compiler warnings. This includes
linting, deprecation notices, and other compiler warnings that are best
detected by the `compile` function and don't require the partial
evalutaion of the flychecker.
The (undef rule :tag) combinator lets a user "scope" tagged captures.
After the rule has matched, all captures with tag :tag can no longer be
refered to by their tag. However, such captures from outside
rule are kept as is. If no tag is given, all tagged captures from rule
are unreferenced. Note that this doesn't `drop` the captures, merely
removes their association with the tag. This means subsequent calls to
`backref` and `backmatch` will no longer "see" these tagged captures.
Keep a separate stack for tagged references. May cause pegs to
use more memory but makes the backref and backmatch features much more
powerful.
Also disables the second stack if backref and backmatch are not used in the peg.
These capture the line and column number of the current position
in the matched text. This is useful for error reporting as well
as indentation checking.
This works by lazily creating an index on first use that stores all
newline character indices in order. We can then do a binary search on
this to get both line number and column number in log(n) time.
This is good enough for most use cases and doesn't slow down the common case at all
- these will not be commonly used patterns in a hot loop so it is not worth to try and
optimize this at all. Constant time look up should be possible but at
the cost of complicating code and slowing down all matching to check for
new lines.
Inpsired by the REBOL operators of the same name, these
combinators match bytes up to or inculding a given pattern.
(to patt) is (almost) equalivalent to (any (if-not patt 1)), and
(thru patt) is equivalent to (* (to patt) patt). The one difference
is that if the end of the input is reached and patt is not
matched, the entire pattern does not match.
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.
This means we can add new properties to abstract types without
breaking old code. We can also make simple abstract types without
needing to add many NULL fields to the type.
Also make integer to size_t casts explicit rather than relying on
int32_t * sizeof(x) = size_t. This is kind of a personal preference for
this problem.
Because we use an amalgated build, feature
test macros should be set in a single file that
is included before any other headers, and is placed
at the top of the amalgamated build.
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.
