update notes

janet/clj-loop.janet

@@ -1,49 +0,0 @@
-(defmacro clj-loop 
-	``A drop-in replacement for Clojure's loop form. Useful for the current project of converting Clojure code to Janet.
-	``
-	[bindings & body]
-		(assert (even? (length bindings)) "Binding tuple must have an even number of terms")
-		(def names @[])
-		(def args @[])
-		(loop [i :range [0 (length bindings)]]
-			(if (even? i)
-				(array/push names (get bindings i))
-				(array/push args (get bindings i))))
-		~(do (defn recur [,;names] ,;body) (recur ,;args)))
-
-(defmacro defn+
-	[name & clauses]
-	~(defn ,name [& args] 
-		(print "before do")
-		(do
-			(def arities @{})
-			(def clauses ,clauses)
-			(def bindingses (map first clauses))
-			(def bodies (map |(slice $ 1) clauses))
-			(print "before loop")
-			(loop [i :range [0 (length clauses)]]
-				(def bindings (get bindingses i))
-				(def arity (length bindings))
-				(assert (not (get arities i)) "Clauses must have different arities")
-				(def body (get bodies i))
-				(def clause ~(fn ,name ,bindings ,;body))
-				(put $arities arity clause))
-			(print "before quasiquote")
-			(fn [& args]
-				(def arity (length args))
-				(def clause (get arities arity))
-				(assert clause "No clause with that arity")	
-				(clause ;args)))))
-
-(defn+ add
-	([] 0)
-	([x] x)
-	([x y] (+ x y)))
-
-(macex1 
-'(defn+ add
-	([] 0)
-	([x] x)
-	([x y] (+ x y))))
-
-

janet/myparser.janet

@@ -1,393 +0,0 @@
-(comment
-So the thing here is that this is a much, much simpler version of the rather unweildy Clojure parser framework I wrote. This leans pretty hard on the Janet PEG framework, but is also bespoke for my purposes here.
-
-This lets me parse not raw text, but scanned tokens, which makes parsing a much easier lift. Also, it lets me do things like insert :break tokens, which really helps manage collection types and blocks.
-
-At current, I do need to shift to returning a data structure rather than `nil`s and `true`s. That way, I can advance the parser by a certain amount, however much a passing test-rule would consume.
-
-Do I really need to optimize this? I don't think so: we can do that later. I could store various information on stacks.
-
-Alternately, returning data structures may well complicate things: KISS!
-
-The idea, however, is that Jesus: we must not have test-rule and apply-rule: combinators without a fixed advance amount can't work that way. So we have only `apply-rule`, which `advance`s the parser by however much should be consumed. BUT! We can always, and ought wherever we might, stash the origin index and roll back any changes (i.e. in `!` and `*`)
-
-)
-
-(defn pprint [x] (printf "%M" x))
-
-(os/cd "janet") ### XXX: to remove, repl only
-(import ./scanner :prefix "")
-
-(defn new-parser 
-	``
-	Creates a new parser from a list of tokens. A parser has three fields in addition to `:tokens`:
-	:i the index, in the list of tokens, of the current token
-	:errors an array of errors, treated like a stack
-	:captured an array of captures (tokens or arrays of tokens), treated like a stack.
-	``
-	[{:tokens tokens}]
-		@{:tokens tokens :i 0 :errors @[] :captured @[]})
-
-(defn pop-to 
-	"Pops items from a stack until it contains `len` items. Returns the stack."
-	[stack len]
-		(assert (>= len 0))
-		(while (< len (length stack)) (array/pop stack))
-		stack)
-
-(defn popn 
-	"Pops n items from a stack. Returns the stack."
-	[stack n]
-		(loop [_ :range [0 n]] (array/pop stack))
-		stack)
-
-(defn current "Returns the current token." [{:tokens tokens :i i}] (get tokens i))
-
-(defn previous "Returns the token before the current token." [{:tokens tokens :i i}] (get tokens (dec i)))
-
-(defn next "Returns the token after the current token." [{:tokens tokens :i i}] (get tokens (inc i)))
-
-(def add +) ### I `def` `+` later; stash this
-
-(defn advance 
-	"Advances the parser by `count`, or 1 if count is not supplied."
-	[parser] (update parser :i inc))
-
-(defn stash 
-	"Stashes a parser state: captures the current index, error, and capture stacks."
-	[{:i i :errors errs :captured cap}]
-		{:i i :err-len (length errs) :cap-len (length cap)})
-
-(defn restore 
-	"Restores the parser to a stashed state: resets :i, pops any new errors and captures off their stacks."
-	[parser state]
-		(def {:i i :err-len err-len :cap-len cap-len} state)
-		(def {:errors errors :captured captured} parser)
-		(put parser :i i)
-		(pop-to errors err-len)
-		(pop-to captured cap-len)
-		parser)
-
-(defn at "Returns the token at index i." [parser i] (get (get parser :tokens) i))
-
-(defn capture "Captures the last token." [parser] (update parser :captured array/push (previous parser)))
-
-(defn apply-keyword 
-	"Applies a keyword-based rule. Consumes the passing token."
-	[kw parser]
-	(def curr (current parser))
-	(def type (get curr :type))
-	(if (= kw type)
-		(do
-			(advance parser)
-			true)
-		nil))
-
-(defn apply-table 
-	"Applies a table-based rule."
-	[rule parser]
-	(def curr (current parser))
-	(def rule-fn (get rule :rule))
-	(rule-fn parser))
-
-(defn apply-rule 
-	"Applies a rule: if the rule passes, consume all passing tokens and return true. If the rule fails, do nothing, returning `nil`."
-	[rule parser]
-	(case (type rule)
-		:keyword (apply-keyword rule parser)
-		:table (apply-table rule parser)
-		(error (string "unknown parser type: " (type rule)))))
-
-(defn name 
-	"Returns the name of a rule. Use this instead of (get rule :name), since bare keywords are also valid rules."
-	[rule]
-	(case (type rule)
-		:keyword rule
-		:table (rule :name)))
-
-(defn rename 
-	"Renames a rule. By convention, rule names are keywords."
-	[rule name] (put rule :name name))
-
-### As noted above: we should not use this
-### Instead, combinators which might not advance should stash state
-### These are: !, *, ...?
-(defn test 
-	"Tests a rule: returns whether a rule passes but does not consume any tokens."
-	[rule parser]
-	(def origin (stash parser))
-	(def result (apply-rule rule parser))
-	(restore parser origin)
-	result)
-
-(defn ! 
-	"Not: negates a rule. If the rule passes, does nothing, returns `nil`. If the rule fails, advances the parser a single token, returns true. Works well only for single token rules."
-	[rule]
-	@{:name (keyword (string "!" (name rule)))
-		:rule (fn !* [parser]
-			(def origin (stash parser))
-			(def result (apply-rule rule parser))
-			(restore parser origin)
-			(if-not result
-				(do (advance parser) true)
-				nil))})
-
-(defn <- 
-	"Capture: if the rule matches, consumes the token and pushes it to the capture stack. If the rule does not match, does nothing."
-	[rule]
-	@{:name (keyword (string "<-" (name rule)))
-		:rule (fn <-* [parser]
-			(def origin (stash parser))
-			(def result (apply-rule rule parser))
-			(if result (capture parser))
-			result)})
-
-(defn + 
-	"Choose a rule: matches if any one of the rules is matched. Order matters: rules are evaluated in order. It's useful to put any errors last."
-	[& rules]
-	@{:name (keyword (string/join (map name rules) "+"))
-		:rule (fn +* [parser]
-			(var passing nil)
-			(def origin (stash parser))
-			(loop [rule :in rules :while (not passing)]
-				(restore parser origin)
-				(set passing (apply-rule rule parser)))
-			(if-not passing (restore parser origin))
-			passing)})
-
-(defn unreachable [&] (error "reached the unreachable"))
-
-(defmacro declare [& names]
-	(def bindings @[])
-	(loop [name :in names]
-		(def binding ~(var ,name @{:name ,(keyword name) :rule unreachable}))
-		(array/push bindings binding))
-	~(upscope ,;bindings))
-
-(defmacro defp [name rule]
-	(if (dyn name)
-		~(set ,name (put ,name :rule (,rule :rule)))
-		~(var ,name (rename ,rule ,(keyword name)))))
-
-(comment (defn panic
-	[rule &opt msg]
-	@{:name (keyword (string "panic-" (name rule)))
-		:rule (fn panic* [parser]
-			(print "panicking!")
-			(def origin (current parser))
-			(var passing false)
-			(def skipped @[])
-			(while (not passing)
-				(array/push skipped (current parser))
-				(advance parser)
-				(set passing (apply-rule rule parser)))
-			(print "looped")
-			(def the-error @{:type :error :token origin :msg msg :skipped skipped})
-			(array/push (parser :errors) the-error)
-			(array/push (parser :captured) the-error)
-			true
-		)}))
-
-# If we wanted to be robust, we wouldn't hard-code this
-# To consider: use a stack of "panic-until" on a parser to dynamically decide how far to panic
-(defp stop (+ :newline :semicolon :break))
-
-(defn panic 
-	"Panics the parser, consuming all tokens until the rule matches (including the match). It also adds an error node to both the capture and the error stacks."
-	[parser expected]
-		(print "panic! in the parser")
-		(def origin (current parser))
-		(var passing false)
-		(def skipped @[])
-		(while (not passing)
-			(array/push skipped (current parser))
-			(advance parser)
-			(set passing (apply-rule stop parser))
-		(print "phew; I'm done panicking")
-		(pprint (current parser))
-		(def the-error {:type :error :expected expected :token origin :skipped skipped})
-		(array/push (parser :errors) the-error)
-		(array/push (parser :captured) the-error)
-		(error parser)))
-
-(defn *
-	"Sequences rules: matches if all rules are matched, in sequence."
-	[& rules]
-	@{:name (keyword (string/join (map name rules) "*"))
-		:rule (fn ** [parser]
-			(print "applying sequence")
-			(var passing true)
-			(def origin (stash parser))
-			(pprint origin)
-			(var failing nil)
-			(var passing true)
-			(loop [rule :in rules :while passing]
-				(def pass? (apply-rule rule parser))
-				(when (not pass?) 
-					(set failing rule)
-					(set passing false)))
-			# this isn't the right thing to do: don't back out, panic!
-			# (when (not passing) (restore parser origin))
-			(if passing
-				passing
-				(panic parser (string "expected " (name failing)))))})
-## next problem: where do we back out to, and how?
-## the answer: an "anchor" point, where we `(try) something, and if it panics, start up with another line; in a block it will be line; in a script it will be toplevel`
-## maybe terms in a tuple, list, dict
-## it seems noteworthy that the things we want to return to are all either "any" or "some", and all either end with a newline or a break
-## they're not all either any or some (empty data structures, but lines in blocks and scripts)
-## also: there's a finite number of possibilities for any of them:
-## another well-formed term, or the end of the item
-## consider:
-(comment
-(defp tuple-term (nonbinding (some separator)))
-(defp tuple-expr (order-1 (<- :lparen) (any separator) (any! tuple-term separator) (:rparen)))
-)
-## the tuple-term can be the anchor point
-## also, in this case, we panic until a *separator*, not a *terminator*
-## that suggests we need a panic-until parameter, rather than the hardcoded stop
-## is this right?
-
-
-(comment (defn order-1 [& rules]
-	@{:name (keyword (string/join (map name rules) "*"))
-		:rule (fn order-1 [parser]
-			(def result (test (first rules) parser))
-			(if result
-				(apply-rule (order-0 ;rules)) ### compile error: unknown symbol order-0
-				nil))}))
-
-(defn capture-group
-	"Takes a parser and an origin state: takes everything captured since the origin, gathers it up in a single array, pops it all off the capture stack, and pushes the gathered captures back on the stack."
-	[parser origin]
-		(def from (get origin :cap-len))
-		(def captured (get parser :captured))
-		(def grouped (array/slice captured from -1))
-		(pop-to captured from)
-		(array/push captured grouped)
-		captured)
-
-(defn & 
-	"Groups rules: pops all captured patterns and pushes them on the captured stack as a single array."
-	[rule]
-	@{:name (keyword (string "&" (name rule)))
-		:rule (fn &* [parser]
-			(def origin (stash parser))
-			(def result (apply-rule rule parser))
-			(if result
-				(do
-					(capture-group parser origin)
-					true)
-				(do
-					(restore parser origin)
-					nil)))})
-
-(defn fn-name 
-	"Returns the name of a function."
-	[f]
-		(def rep (string f))
-		(string/slice rep 10 -2))
-
-(defn / 
-	"Substitution: takes a rule and a function, and applies the function to any captures arising from the rule; the captures are individual parameters to the function."
-	[rule f]
-	@{:name (keyword (string (name rule) "/" (fn-name f)))
-		:rule (fn /* [parser]
-			(def origin (stash parser))
-			(def captured (get parser :captured))
-			(def result (apply-rule (& rule) parser))
-			(if result
-				(do
-					(def grouped (array/pop captured))
-					(def applied (f ;grouped))
-					(array/push captured applied)
-					true)
-				(do
-					(restore parser origin)
-					nil)))})
-
-(defn any 
-	"Matches zero or more instances of a rule."
-	[rule] 
-	@{:name (keyword (string "any-" (name rule)))
-		:rule (fn any* [parser]
-			(var result true)
-			(while result
-				(set result (apply-rule rule parser)))
-			true)})
-
-(defn some 
-	"Matches one or more instances of a rule."
-	[rule]
-	@{:name (keyword (string "some-" (name rule)))
-		:rule (fn some* [parser]
-			(def origin (stash parser))
-			(def result (apply-rule rule parser))
-			(if result
-				(do
-					(apply-rule (any rule) parser)
-					true)
-				(do
-					(restore parser origin)
-					nil)))})
-
-(defn parse [tokens rule]
-	(def parser (new-parser tokens))
-	(try 
-		(do (apply-rule rule parser) parser)
-		([err] err)))
-
-(upscope #XXX for easier repl use
-
-(defn literal->ast [token] {:type (get token :type) :data (get token :literal) :token token})
-
-(defn word->ast [token] {:type (get token :type) :data (get token :lexeme) :token token})
-
-(defn tuple->ast [origin & tokens] {:type :tuple :data tokens :token origin})
-
-(defn if->ast [origin & tokens] {:type :if :data tokens :token origin})
-
-(declare expression simple nonbinding)
-
-(defp separator (some (+ :newline :comma :break)))
-(defp separators? (any (+ :newline :comma :break)))
-(defp terminator (some (+ :newline :semicolon :break)))
-(defp terminators? (any (+ :newline :semicolon :break)))
-(defp nls? (any :newline))
-
-(defp atom (/ (<- (+ :nil :true :false :number :keyword :string)) literal->ast))
-(defp word (/ (<- :word) word->ast))
-
-(defp tuple-term (* nonbinding separator))
-(defp tuple-literal (/ (* (<- :lparen) separators? (any tuple-term) :rparen) tuple->ast))
-
-(defp if-expr (/ (* (<- :if) simple nls? :then nonbinding nls? :else nonbinding) if->ast))
-
-# (defp root (<- (+ :word :keyword)))
-# (defp follow (<- (+ :keyword :arg-tuple)))
-# (defp synthetic (& (* root (some follow))))
-
-(defp simple (+ atom word tuple-literal))
-(defp nonbinding (+ atom word tuple-literal))
-(defp expression (+ atom word tuple-literal))
-(defp line (* expression (some terminator)))
-# (defp toplevel)
-(defp script (some line))
-
-(def source
-``
-if (:)foo then :bar else :baz
-
-``
-)
-
-(-> (scan source) (parse if-expr) pprint)
-)
-
-(comment
-
-Okay, so I'm trying to figure out how to manage panics in this declarative (not recursive-descent) parser.
-The question is how to do the thing where we pop out of the stack up to the most relevant rule.
-Given that we may have deeply nested rules, we either want:
-	- A stack of rules in the parser, which
-)

janet/peg-parser.janet

@@ -1,104 +0,0 @@
-(defn ->kw [kw-str]
-	(keyword (slice kw-str 1)))
-
-(defn word [str] [:word str])
-
-(defn num [num] [:number (scan-number num)])
-
-(defn kw [_ kw] [:keyword (->kw kw)])
-
-(defn str [str] [:string str])
-
-(defn bool [bool] (if (= bool "true") [:boolean true] [:boolean false]))
-
-(defn nill [_] [:nil nil])
-
-(defn not-empty? [x] (not (empty? x)))
-
-(defn ifl [args] [:if ;args])
-
-(defn letl [args] [:let ;args])
-
-(defn block [args] [:block args])
-
-(def errors @[])
-
-(defn ? [x default] (if (nil? x) default x))
-
-(defn panic [& args]
-	(def info (filter |(not= "" $) args))
-	(def [msg line col source] info)
-	(def error {:msg msg :line line :col col :source (? source "")})	
-	(array/push errors error)
-	[:error error]
-)
-
-(do
-(def ludus-grammar
-	~{:nil (cmt (<- "nil") ,nill)
-		:true (cmt (<- "true") ,bool)
-		:false (cmt (<- "false") ,bool)
-		:comment (* "&" (any (if-not (+ "\n" -1) 1)))
-		:wordchars (+ :w (set "_-/*?!"))
-		:reserved (+ "if" "then" "else" "let")
-		:word (cmt (<- (if-not :reserved (* (range "az") (any :wordchars)))) ,word)
-		:keyword (cmt (<- (* ":" :word)) ,kw)
-		:hex (range "09" "af" "AF")
-		:escape (* "\\" (+ (set `"'0?\abefnrtvz`)
-                       (* "x" :hex :hex)
-                       (* "u" [4 :hex])
-                       (* "U" [6 :hex])
-                       (error (constant "bad escape"))))
-		:string (cmt (* "\"" (<- (any (+ :escape (if-not "\"" 1)))) "\"") ,str)
-		:int (* (? "-") (range "19") (any (+ "_" (range "09"))))
-		:float (* (? "-") (+ :int "0") "." (any (+ "_" (range "09"))))
-		:zero "0"
-		:number (cmt (<- (+ :float :int :zero)) ,num)
-		:comment (* "&" (any (if-not (+ "\n" -1) 1)))
-		:atom (+ :nil :true :false :keyword :number :word)
-		:newline "\n"
-		:terminator (* (any :ws) (some (+ :newline ";")))
-		:separator (* (any :ws) (some (+ :newline ",")))
-		:ws (any (+ :comment (set " \t")))
-		:simple (+ :atom :string :word (* (constant "expected simple" :err-msg) :panic))
-		:then (+ (* (+ (some :ws) (any :newline)) (any :ws) "then" (some :ws)) (* (constant "expected then" :err-msg) :panic))
-		:else (+ (* (+ (some :ws) (any :newline)) (any :ws) "else" (some :ws)) (* (constant "expected else" :err-msg) :panic))
-		:panic (cmt (* (<- (-> :err-msg)) (<- (line)) (<- (column)) (<- (* (any (if-not (+ "\n" -1) 1))))) ,panic)
-		:non-binding (+ :atom :word :string :if :block 
-			(* (constant "expected non-binding" :err-msg) :panic))
-		:tuple-term (* :number (some :separator))
-		:tuple (* "(" (any :separator) (any :tuple-term) ")")
-		:block (cmt (group (* "{" (some :line) (? :expression) "}")) ,block)
-		:if (cmt (group (* "if" (some :ws) :simple :then :non-binding :else :non-binding)) ,ifl)
-		:pattern (+ :atom :string (* (constant "expected pattern") :panic))
-		:equals (* (any :ws) "=" (any :ws))
-		:let (cmt (group (* "let" (some :ws) :pattern :equals :non-binding)) ,letl)
-		:expression (+ :atom :string :block :if :let
-			(* (constant "expected expression" :err-msg) :panic))
-		:empty (* :ws :terminator)
-		:line (* :ws :expression :ws :terminator)
-		:main :tuple})
-		
-(def simple-tuple ~{
-	:value (<- (range "az"))
-	:separator (+ "," "\n")
-	:ws (any (set " \t"))
-	:term (* :ws :value :ws :separator)
-	:tuple (group (* "(" (any :term) (? :value) :ws ")"))
-	:main :tuple
-})
-
-
-# :empty/:line/:block are still giving me grief
-# also, somehow line & column numbers ar
-(def source
-``
-(   a, b  ,c,d   )
-``
-)
-
-
-(peg/match simple-tuple source)
-)
-
-

janet/validate.janet

@@ -4,21 +4,21 @@
 
 Tracking here, before I start writing this code, the kinds of validation we're hoping to accomplish:
 
-* [x] splats come at the end of list, tuple, and dict patterns
-* [x] no unbound names
-* [x] no re-bound names
-* [x] no unbound names with `use` forms
 * [ ] first-level property access with pkg, e.g. `Foo :bar`--bar must be on Foo
-* [x] recur in tail position in `loop` forms
+ - [ ] accept pkg-kws
-* [x] recur not called outside of `loop` forms
 * [x] `loop` form arity checking
 * [x] arity checking of explicit named function calls
-* [ ] flag tail calls
+* [x] flag tail calls
+* [x] no re-bound names
+* [x] no unbound names
+* [x] no unbound names with `use` forms
+* [x] recur in tail position in `loop` forms
+* [x] recur not called outside of `loop` forms
+* [x] splats come at the end of list, tuple, and dict patterns
 
 Imports are for a later iteration of Ludus:
 * [ ] no circular imports DEFERRED
 * [ ] correct imports DEFERRED
-
 )
 
 
@@ -290,7 +290,14 @@ Imports are for a later iteration of Ludus:
 (defn- pkg-root [validator])
 
 # * [ ] flag tail calls (where last term is not-partial args)
-(defn- tail-call [validator])
+(defn- tail-call [validator]
+ (def ast (validator :ast))
+ (when (ast :partial) (break validator))
+ (def status (validator :status))
+ (when (not (status :tail)) (break validator))
+ (def data (ast :data))
+ (def args (last data))
+ (set (args :tail-call) true))
 
 # * [ ] arity checking if first term is name that resolves to a function and args aren't partial
 # XXX: now just check number of args against arity map
@@ -579,16 +586,16 @@ Imports are for a later iteration of Ludus:
 (do
 #(comment
 (def source `
-fn foo {
+fn bar () -> :bar
- () -> :bar
+fn foo () -> match :foo with {
- (x) -> :foo
+ a -> bar ()
- (x, y, ...z) -> :baz
+ b -> :baz
 }
-foo (4)
 `)
 (def scanned (s/scan source))
 (def parsed (p/parse scanned))
 (def validator (new-validator parsed))
 (pp validator)
-((validate validator) :errors)
+(validate validator) 
+(pp parsed)
 )