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diff --git a/luxc/src/lux/reader.clj b/luxc/src/lux/reader.clj
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+++ b/luxc/src/lux/reader.clj
@@ -0,0 +1,141 @@
+;;  Copyright (c) Eduardo Julian. All rights reserved.
+;;  This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0.
+;;  If a copy of the MPL was not distributed with this file,
+;;  You can obtain one at http://mozilla.org/MPL/2.0/.
+
+(ns lux.reader
+  (:require [clojure.string :as string]
+            clojure.core.match
+            clojure.core.match.array
+            [lux.base :as & :refer [defvariant |do return* return fail* |let |case]]))
+
+;; [Tags]
+(defvariant
+  ("No" 1)
+  ("Done" 1)
+  ("Yes" 2))
+
+;; [Utils]
+(defn ^:private with-line [body]
+  (fn [state]
+    (|case (&/get$ &/$source state)
+      (&/$Nil)
+      (fail* "[Reader Error] EOF")
+
+      (&/$Cons [[file-name line-num column-num] line]
+               more)
+      (|case (body file-name line-num column-num line)
+        ($No msg)
+        ((&/fail-with-loc msg) state)
+
+        ($Done output)
+        (return* (&/set$ &/$source more state)
+                 output)
+
+        ($Yes output line*)
+        (return* (&/set$ &/$source (&/$Cons line* more) state)
+                 output))
+      )))
+
+(defn ^:private with-lines [body]
+  (fn [state]
+    (|case (body (&/get$ &/$source state))
+      (&/$Right reader* match)
+      (return* (&/set$ &/$source reader* state)
+               match)
+
+      (&/$Left msg)
+      ((&/fail-with-loc msg) state)
+      )))
+
+(defn ^:private re-find! [^java.util.regex.Pattern regex column ^String line]
+  (let [matcher (doto (.matcher regex line)
+                  (.region column (.length line))
+                  (.useAnchoringBounds true))]
+    (when (.find matcher)
+      (.group matcher 0))))
+
+;; [Exports]
+(defn read-regex [regex]
+  (with-line
+    (fn [file-name line-num column-num ^String line]
+      (if-let [^String match (re-find! regex column-num line)]
+        (let [match-length (.length match)
+              column-num* (+ column-num match-length)]
+          (if (= column-num* (.length line))
+            ($Done (&/T [(&/T [file-name line-num column-num]) true match]))
+            ($Yes (&/T [(&/T [file-name line-num column-num]) false match])
+                  (&/T [(&/T [file-name line-num column-num*]) line]))))
+        ($No (str "[Reader Error] Pattern failed: " regex))))))
+
+(defn read-regex+ [regex]
+  (with-lines
+    (fn [reader]
+      (loop [prefix ""
+             reader* reader]
+        (|case reader*
+          (&/$Nil)
+          (&/$Left "[Reader Error] EOF")
+
+          (&/$Cons [[file-name line-num column-num] ^String line]
+                   reader**)
+          (if-let [^String match (re-find! regex column-num line)]
+            (let [match-length (.length match)
+                  column-num* (+ column-num match-length)
+                  prefix* (if (= 0 column-num)
+                            (str prefix "\n" match)
+                            (str prefix match))]
+              (if (= column-num* (.length line))
+                (recur prefix* reader**)
+                (&/$Right (&/T [(&/$Cons (&/T [(&/T [file-name line-num column-num*]) line])
+                                         reader**)
+                                (&/T [(&/T [file-name line-num column-num]) prefix*])]))))
+            (&/$Left (str "[Reader Error] Pattern failed: " regex))))))))
+
+(defn read-text [^String text]
+  "(-> Text (Reader Text))"
+  (with-line
+    (fn [file-name line-num column-num ^String line]
+      (if (.startsWith line text column-num)
+        (let [match-length (.length text)
+              column-num* (+ column-num match-length)]
+          (if (= column-num* (.length line))
+            ($Done (&/T [(&/T [file-name line-num column-num]) true text]))
+            ($Yes (&/T [(&/T [file-name line-num column-num]) false text])
+                  (&/T [(&/T [file-name line-num column-num*]) line]))))
+        ($No (str "[Reader Error] Text failed: " text))))))
+
+(defn read-text? [^String text]
+  "(-> Text (Reader (Maybe Text)))"
+  (with-line
+    (fn [file-name line-num column-num ^String line]
+      (if (.startsWith line text column-num)
+        (let [match-length (.length text)
+              column-num* (+ column-num match-length)]
+          (if (= column-num* (.length line))
+            ($Done (&/T [(&/T [file-name line-num column-num]) true (&/$Some text)]))
+            ($Yes (&/T [(&/T [file-name line-num column-num]) false (&/$Some text)])
+                  (&/T [(&/T [file-name line-num column-num*]) line]))))
+        ($Yes (&/T [(&/T [file-name line-num column-num]) false &/$None])
+              (&/T [(&/T [file-name line-num column-num]) line]))))))
+
+(defn from [^String name ^String source-code]
+  (let [lines (string/split-lines source-code)
+        indexed-lines (map (fn [line line-num]
+                             (&/T [(&/T [name (inc line-num) 0])
+                                   line]))
+                           lines
+                           (range (count lines)))]
+    (reduce (fn [tail head] (&/$Cons head tail))
+            &/$Nil
+            (reverse indexed-lines))))
+
+(defn with-source [name content body]
+  (fn [state]
+    (|let [old-source (&/get$ &/$source state)]
+      (|case (body (&/set$ &/$source (from name content) state))
+        (&/$Left error)
+        (&/$Left error)
+
+        (&/$Right state* output)
+        (&/$Right (&/T [(&/set$ &/$source old-source state*) output]))))))