diff --git a/src/ludus/parser.clj b/src/ludus/parser.clj index 52d0fec..c8dacce 100644 --- a/src/ludus/parser.clj +++ b/src/ludus/parser.clj @@ -61,7 +61,7 @@ (defn- panic ([parser message] (panic parser message sync-on)) ([parser message sync-on] - (println (str "PANIC!!! in the parser" message)) + (println (str "PANIC!!! in the parser: " message)) (let [ sync-on (conj (if (set? sync-on) sync-on #{sync-on}) ::token/eof) origin (current parser) @@ -360,11 +360,11 @@ ;; TODO: Fix failure case here (defn- parse-if [parser] (let [ - if-expr (parse-expr (advance parser)) + if-expr (parse-expr (advance parser) #{::token/then ::token/newline}) then (expect ::token/then "Expected then" (accept ::token/newline if-expr)) then-expr (parse-expr then) else (expect ::token/else "Epected else" (accept ::token/newline then-expr)) - else-expr (parse-expr else) + else-expr (parse-expr else #{::token/else ::token/newline}) results (map #(get-in % [::ast ::ast/type]) [if-expr then then-expr else else-expr]) ] (if (some #(= ::ast/poison %) results) @@ -377,55 +377,58 @@ })) )) -(defn- parse-expr [parser] - (let [token (current parser)] - (case (::token/type token) - - (::token/number ::token/string) - (parse-atom parser) - - ::token/keyword (let [next (peek parser) - type (::token/type next)] - (if (= type ::token/lparen) - (parse-synthetic parser) - (parse-atom parser))) - - ::token/word (let [next (peek parser) - type (::token/type next)] - (case type - (::token/lparen ::token/keyword) (parse-synthetic parser) - (parse-word parser))) - - (::token/nil ::token/true ::token/false) - (parse-atomic-word parser) - - ::token/lparen (parse-tuple parser) - - ::token/lbracket (parse-list parser) - - ::token/startset (parse-set parser) - - ::token/lbrace (parse-block parser) - - ::token/let (parse-let* parser) - - ::token/if (parse-if parser) - - ::token/error (panic parser (:message token)) - - (::token/rparen ::token/rbrace ::token/rbracket) - (panic parser (str "Unbalanced enclosure: " (::token/lexeme token))) - - (::token/semicolon ::token/comma) - (panic parser (str "Unexpected delimiter: " (::token/lexeme token))) - - (panic parser "Expected expression") - - ))) +(defn- parse-expr + ([parser] (parse-expr parser sync-on)) + ([parser sync-on] (let [token (current parser)] + (case (::token/type token) + + (::token/number ::token/string) + (parse-atom parser) + + ::token/keyword (let [next (peek parser) + type (::token/type next)] + (if (= type ::token/lparen) + (parse-synthetic parser) + (parse-atom parser))) + + ::token/word (let [next (peek parser) + type (::token/type next)] + (case type + (::token/lparen ::token/keyword) (parse-synthetic parser) + (parse-word parser))) + + (::token/nil ::token/true ::token/false) + (parse-atomic-word parser) + + ::token/lparen (parse-tuple parser) + + ::token/lbracket (parse-list parser) + + ::token/startset (parse-set parser) + + ::token/lbrace (parse-block parser) + + ::token/let (parse-let* parser) + + ::token/if (parse-if parser) + + ::token/error (panic parser (:message token)) + + (::token/rparen ::token/rbrace ::token/rbracket) + (panic parser (str "Unbalanced enclosure: " (::token/lexeme token))) + + (::token/semicolon ::token/comma) + (panic parser (str "Unexpected delimiter: " (::token/lexeme token))) + + (panic parser "Expected expression" sync-on) + + )))) (do (def pp pp/pprint) - (def source "if *else then bar else baz") + (def source "if + then bar + else baz") (def lexed (scanner/scan source)) (def tokens (:tokens lexed)) (def p (parser tokens)) @@ -437,7 +440,7 @@ (println "*** *** NEW PARSE *** ***") (-> p - (parse-script) + (parse-if) (::ast) (pp) )