Fully fix lets; re-discover unfinished business with ifs

This commit is contained in:
Scott Richmond 2022-03-12 14:39:27 -05:00
parent 1a1f720358
commit 21bef073d0

View File

@ -61,7 +61,7 @@
(defn- panic (defn- panic
([parser message] (panic parser message sync-on)) ([parser message] (panic parser message sync-on))
([parser message sync-on] ([parser message sync-on]
(println "PANIC!!! in the parser") (println (str "PANIC!!! in the parser" message))
(let [ (let [
sync-on (conj (if (set? sync-on) sync-on #{sync-on}) ::token/eof) sync-on (conj (if (set? sync-on) sync-on #{sync-on}) ::token/eof)
origin (current parser) origin (current parser)
@ -86,6 +86,15 @@
(advance) (advance)
(panic message tokens))))) (panic message tokens)))))
(defn- expect* [tokens message parser]
(let [curr (current parser)
tokens (if (set? tokens) tokens #{tokens})
type (::token/type curr)]
(if (contains? tokens type)
{:success true :parser (advance parser)}
{:success false :paser (panic (advance parser) message)}
)))
(defn- accept [tokens parser] (defn- accept [tokens parser]
(let [curr (current parser) (let [curr (current parser)
tokens (if (set? tokens) tokens #{tokens}) tokens (if (set? tokens) tokens #{tokens})
@ -327,10 +336,11 @@
:pattern (::ast pattern) :expr (::ast expr)}))) :pattern (::ast pattern) :expr (::ast expr)})))
(defn- parse-assignment [parser] (defn- parse-assignment [parser]
(let [assignment (expect ::token/equals "Expected assignment" parser)] (let [assignment (expect* ::token/equals "Expected assignment" parser)
(if (poisoned? assignment) success (:success assignment)]
assignment (if success
(parse-let-expr assignment parser)))) (parse-let-expr (:parser assignment) parser)
(panic parser "Expected assignment"))))
(defn- parse-let [parser] (defn- parse-let [parser]
(let [pattern (parse-pattern (advance parser))] (let [pattern (parse-pattern (advance parser))]
@ -340,6 +350,14 @@
) )
)) ))
(defn- parse-let* [parser]
(let [pattern (parse-pattern (advance parser))]
(parse-assignment pattern)))
(defn- parse-if* [parser]
)
;; TODO: Fix failure case here
(defn- parse-if [parser] (defn- parse-if [parser]
(let [ (let [
if-expr (parse-expr (advance parser)) if-expr (parse-expr (advance parser))
@ -350,9 +368,9 @@
results (map #(get-in % [::ast ::ast/type]) [if-expr then then-expr else else-expr]) results (map #(get-in % [::ast ::ast/type]) [if-expr then then-expr else else-expr])
] ]
(if (some #(= ::ast/poison %) results) (if (some #(= ::ast/poison %) results)
(println ::ast/poison) (println ::ast/poison) ;; TODO: FIX THIS
(assoc else-expr ::ast { (assoc else-expr ::ast {
::ast/type ::ast/let ::ast/type ::ast/if
:if-expr (::ast if-expr) :if-expr (::ast if-expr)
:then-expr (::ast then-expr) :then-expr (::ast then-expr)
:else-expr (::ast else-expr) :else-expr (::ast else-expr)
@ -389,7 +407,7 @@
::token/lbrace (parse-block parser) ::token/lbrace (parse-block parser)
::token/let (parse-let parser) ::token/let (parse-let* parser)
::token/if (parse-if parser) ::token/if (parse-if parser)
@ -407,8 +425,7 @@
(do (do
(def pp pp/pprint) (def pp pp/pprint)
(def source "let then = 42 (def source "if *else then bar else baz")
let foo = bar")
(def lexed (scanner/scan source)) (def lexed (scanner/scan source))
(def tokens (:tokens lexed)) (def tokens (:tokens lexed))
(def p (parser tokens)) (def p (parser tokens))