diff options
Diffstat (limited to 'src/clojure_sql/compiler.clj')
| -rw-r--r-- | src/clojure_sql/compiler.clj | 45 |
1 files changed, 34 insertions, 11 deletions
diff --git a/src/clojure_sql/compiler.clj b/src/clojure_sql/compiler.clj index 9ba0c3a..c7f907f 100644 --- a/src/clojure_sql/compiler.clj +++ b/src/clojure_sql/compiler.clj @@ -5,6 +5,12 @@ [clojure-sql.util :as u :refer [named?]] [clojure-sql.writer :as w :refer [return lift p-lift sequence do-m tell >>]])) +(defn no-args-operator-error [op] + (throw (ex-info (str "Argument called with no args doesn't have identity value: " op) + {:operator op}))) + + + (defn add-parentheses [s] (str \( s \))) @@ -39,10 +45,18 @@ ;; Utility functions for the compile-* functions ;; ============================================================== +(def ^:private boolean? (some-fn true? false?)) +(def ^:private regex? (partial instance? (class #""))) +(def ^:private operator-name (some-fn (comp {"$" "~"} name) name)) + (def quote? (comp boolean '#{"quote"} name)) -(def unary? (comp boolean '#{"not" "exists"} name)) -(def binary? (comp boolean '#{"=" "<" ">" "<=" ">=" "is" "in"} name)) -(def operator? (comp boolean '#{"and" "or" "+" "-" "/" "*"} name)) +(def unary? (comp boolean '#{"not" "exists" "-"} name)) +(def binary? (comp boolean '#{"=" "<" ">" "<=" ">=" "is" "in" "like" "~"} name)) +(def n-ary? (comp boolean '#{"and" "or" "+" "-" "/" "*"} name)) +(def operator-identity (comp {"and" true + "or" false + "+" 0 + "*" 1} name)) ;; ============================================================== @@ -64,24 +78,31 @@ (defmulti compile-expression-sequential (fn [db _] db)) (defmethod compile-expression-sequential :default [db ex] (let [compile-exprs #(map (partial compile-expression db) %) - op (name (first ex)) + op-name (operator-name (first ex)) num-args (dec (count ex))] - (-> (condp u/funcall (first ex) + (-> (condp u/funcall op-name quote? (do (assert (= num-args 1) "`quote` must only take one argument") (if (sequential? (second ex)) (compile-expression-list db (second ex)) (>> (tell (second ex)) (return "?")))) - unary? (do (assert (= num-args 1) (str "Unary operator `" op "` must take one argument")) + n-ary? (do-m :let [[op & exprs] (compile-exprs ex)] + vals <- (apply sequence (interpose op exprs)) + (condp = (count vals) + 0 (if-let [id (operator-identity op-name)] + (compile-expression db id) + (no-args-operator-error (name (first ex)))) + 1 (if (unary? op-name) + (do-m compiled-op <- op + (return (str compiled-op (first vals))))) + (return (string/join " " vals)))) + unary? (do (assert (= num-args 1) (str "Unary operator `" (first ex) "` must take one argument")) (do-m :let [exprs (compile-exprs ex)] vals <- (apply sequence exprs) (return (string/join "" vals)))) - binary? (do (assert (= num-args 2) (str "Binary operator `" op "` must take two arguments")) + binary? (do (assert (= num-args 2) (str "Binary operator `" (first ex) "` must take two arguments")) (do-m :let [[op left right] (compile-exprs ex)] vals <- (sequence left op right) (return (string/join " " vals)))) - operator? (do-m :let [[op & exprs] (compile-exprs ex)] - vals <- (apply sequence (interpose op exprs)) - (return (string/join " " vals))) (do-m :let [fn-name (function-name db (first ex)) exprs (compile-exprs (rest ex))] vals <- (apply sequence exprs) @@ -92,12 +113,14 @@ (defmulti compile-expression (fn [db _] db)) (defmethod compile-expression :default [db ex] (condp u/funcall ex + boolean? (return (string/upper-case (str ex))) query? ($add-parentheses (compile-query db ex)) nil? (return "NULL") vector? (return (str (table-name db (first ex)) \. (field-name db (second ex)))) keyword? (return (field-name db ex)) + regex? (>> (tell (str ex)) (return "?")) string? (>> (tell ex) (return "?")) ;;(sql-string db ex) - symbol? (return (string/upper-case (name ex))) + symbol? (return (string/upper-case (operator-name ex))) sequential? (compile-expression-sequential db ex) (return ex))) |