diff --git a/lib/rules.js b/lib/rules.js
index f990f5fc..5f623d0d 100644
--- a/lib/rules.js
+++ b/lib/rules.js
@@ -31,10 +31,12 @@ function unorderedListStyleFor(token) {
   }
 }
 
-// Filters a list of tokens by type
-function filterTokens(tokens, typeA, typeB) {
-  return tokens.filter(function filterToken(token) {
-    return ((token.type === typeA) || (token.type === typeB));
+// Calls the provided function for each matching token
+function filterTokens(tokens, type, callback) {
+  tokens.forEach(function forToken(token) {
+    if (token.type === type) {
+      callback(token);
+    }
   });
 }
 
@@ -42,12 +44,11 @@ function filterTokens(tokens, typeA, typeB) {
 function forEachLine(params, callback) {
   // Identify lines in code blocks
   var codeLines = [];
-  filterTokens(params.tokens, "code_block")
-    .forEach(function forToken(token) {
-      for (var i = token.map[0]; i < token.map[1]; i++) {
-        codeLines.push(i);
-      }
-    });
+  filterTokens(params.tokens, "code_block", function forToken(token) {
+    for (var i = token.map[0]; i < token.map[1]; i++) {
+      codeLines.push(i);
+    }
+  });
   // Identify lines in code fences (with info about transitions)
   var inFence = false;
   params.lines.forEach(function forLine(line, lineIndex) {
@@ -62,13 +63,11 @@ function forEachLine(params, callback) {
 
 // Calls the provided function for each specified inline child token
 function forEachInlineChild(params, type, callback) {
-  filterTokens(params.tokens, "inline")
-    .forEach(function forToken(token) {
-      filterTokens(token.children, type)
-        .forEach(function forChild(child) {
-          callback(child, token);
-        });
+  filterTokens(params.tokens, "inline", function forToken(token) {
+    filterTokens(token.children, type, function forChild(child) {
+      callback(child, token);
     });
+  });
 }
 
 // Calls the provided function for each heading's content
@@ -131,14 +130,13 @@ module.exports = [
     "tags": [ "headers" ],
     "func": function MD001(params, errors) {
       var prevLevel = 0;
-      filterTokens(params.tokens, "heading_open")
-        .forEach(function forToken(token) {
-          var level = parseInt(token.tag.slice(1), 10);
-          if (prevLevel && (level > prevLevel + 1)) {
-            errors.push(token.lineNumber);
-          }
-          prevLevel = level;
-        });
+      filterTokens(params.tokens, "heading_open", function forToken(token) {
+        var level = parseInt(token.tag.slice(1), 10);
+        if (prevLevel && (level > prevLevel + 1)) {
+          errors.push(token.lineNumber);
+        }
+        prevLevel = level;
+      });
     }
   },
 
@@ -165,11 +163,10 @@ module.exports = [
     "tags": [ "headers" ],
     "func": function MD003(params, errors) {
       var style = params.options.style || "consistent";
-      var headings = filterTokens(params.tokens, "heading_open");
-      if ((style === "consistent") && headings.length) {
-        style = headingStyleFor(headings[0]);
-      }
-      headings.forEach(function forToken(token) {
+      filterTokens(params.tokens, "heading_open", function forToken(token) {
+        if (style === "consistent") {
+          style = headingStyleFor(token);
+        }
         if (headingStyleFor(token) !== style) {
           errors.push(token.lineNumber);
         }
@@ -321,8 +318,8 @@ module.exports = [
     "desc": "Dollar signs used before commands without showing output",
     "tags": [ "code" ],
     "func": function MD014(params, errors) {
-      filterTokens(params.tokens, "code_block", "fence")
-        .forEach(function forToken(token) {
+      [ "code_block", "fence" ].forEach(function forType(type) {
+        filterTokens(params.tokens, type, function forToken(token) {
           if (token.content && token.content.split(shared.newLineRe)
             .filter(function filterLine(line) {
               return line;
@@ -332,6 +329,7 @@ module.exports = [
             errors.push(token.lineNumber);
           }
         });
+      });
     }
   },
 
@@ -353,13 +351,12 @@ module.exports = [
     "desc": "Multiple spaces after hash on atx style header",
     "tags": [ "headers", "atx", "spaces" ],
     "func": function MD019(params, errors) {
-      filterTokens(params.tokens, "heading_open")
-        .forEach(function forToken(token) {
-          if ((headingStyleFor(token) === "atx") &&
-              /^#+\s\s/.test(token.line)) {
-            errors.push(token.lineNumber);
-          }
-        });
+      filterTokens(params.tokens, "heading_open", function forToken(token) {
+        if ((headingStyleFor(token) === "atx") &&
+            /^#+\s\s/.test(token.line)) {
+          errors.push(token.lineNumber);
+        }
+      });
     }
   },
 
@@ -382,13 +379,12 @@ module.exports = [
     "desc": "Multiple spaces inside hashes on closed atx style header",
     "tags": [ "headers", "atx_closed", "spaces" ],
     "func": function MD021(params, errors) {
-      filterTokens(params.tokens, "heading_open")
-        .forEach(function forToken(token) {
-          if ((headingStyleFor(token) === "atx_closed") &&
-              (/^#+\s\s/.test(token.line) || /\s\s#+$/.test(token.line))) {
-            errors.push(token.lineNumber);
-          }
-        });
+      filterTokens(params.tokens, "heading_open", function forToken(token) {
+        if ((headingStyleFor(token) === "atx_closed") &&
+            (/^#+\s\s/.test(token.line) || /\s\s#+$/.test(token.line))) {
+          errors.push(token.lineNumber);
+        }
+      });
     }
   },
 
@@ -434,12 +430,11 @@ module.exports = [
     "desc": "Headers must start at the beginning of the line",
     "tags": [ "headers", "spaces" ],
     "func": function MD023(params, errors) {
-      filterTokens(params.tokens, "heading_open")
-        .forEach(function forToken(token) {
-          if (/^\s/.test(token.line)) {
-            errors.push(token.lineNumber);
-          }
-        });
+      filterTokens(params.tokens, "heading_open", function forToken(token) {
+        if (/^\s/.test(token.line)) {
+          errors.push(token.lineNumber);
+        }
+      });
     }
   },
 
@@ -465,16 +460,15 @@ module.exports = [
     "tags": [ "headers" ],
     "func": function MD025(params, errors) {
       var hasTopLevelHeading = false;
-      filterTokens(params.tokens, "heading_open")
-        .forEach(function forToken(token) {
-          if (token.tag === "h1") {
-            if (hasTopLevelHeading) {
-              errors.push(token.lineNumber);
-            } else if (token.lineNumber === 1) {
-              hasTopLevelHeading = true;
-            }
+      filterTokens(params.tokens, "heading_open", function forToken(token) {
+        if (token.tag === "h1") {
+          if (hasTopLevelHeading) {
+            errors.push(token.lineNumber);
+          } else if (token.lineNumber === 1) {
+            hasTopLevelHeading = true;
           }
-        });
+        }
+      });
     }
   },
 
@@ -624,10 +618,9 @@ module.exports = [
     "desc": "Inline HTML",
     "tags": [ "html" ],
     "func": function MD033(params, errors) {
-      filterTokens(params.tokens, "html_block")
-        .forEach(function forToken(token) {
-          errors.push(token.lineNumber);
-        });
+      filterTokens(params.tokens, "html_block", function forToken(token) {
+        errors.push(token.lineNumber);
+      });
       forEachInlineChild(params, "html_inline", function forToken(token) {
         errors.push(token.lineNumber);
       });
@@ -639,21 +632,20 @@ module.exports = [
     "desc": "Bare URL used",
     "tags": [ "links", "url" ],
     "func": function MD034(params, errors) {
-      filterTokens(params.tokens, "inline")
-        .forEach(function forToken(token) {
-          var inLink = false;
-          token.children.forEach(function forChild(child) {
-            if (child.type === "link_open") {
-              inLink = true;
-            } else if (child.type === "link_close") {
-              inLink = false;
-            } else if ((child.type === "text") &&
-                       !inLink &&
-                       /https?:\/\//.test(child.content)) {
-              errors.push(child.lineNumber);
-            }
-          });
+      filterTokens(params.tokens, "inline", function forToken(token) {
+        var inLink = false;
+        token.children.forEach(function forChild(child) {
+          if (child.type === "link_open") {
+            inLink = true;
+          } else if (child.type === "link_close") {
+            inLink = false;
+          } else if ((child.type === "text") &&
+                     !inLink &&
+                     /https?:\/\//.test(child.content)) {
+            errors.push(child.lineNumber);
+          }
         });
+      });
     }
   },
 
@@ -663,11 +655,10 @@ module.exports = [
     "tags": [ "hr" ],
     "func": function MD035(params, errors) {
       var style = params.options.style || "consistent";
-      var horizontalRules = filterTokens(params.tokens, "hr");
-      if ((style === "consistent") && horizontalRules.length) {
-        style = horizontalRules[0].line;
-      }
-      horizontalRules.forEach(function forToken(token) {
+      filterTokens(params.tokens, "hr", function forToken(token) {
+        if (style === "consistent") {
+          style = token.line;
+        }
         if (token.line !== style) {
           errors.push(token.lineNumber);
         }
@@ -739,32 +730,31 @@ module.exports = [
     "desc": "Spaces inside link text",
     "tags": [ "whitespace", "links" ],
     "func": function MD039(params, errors) {
-      filterTokens(params.tokens, "inline")
-        .forEach(function forToken(token) {
-          var inLink = false;
-          var index = 0;
-          var lastChildRightSpaceLineNumber = 0;
-          token.children.forEach(function forChild(child) {
-            if (child.type === "link_open") {
-              inLink = true;
-              index = 0;
-            } else if (child.type === "link_close") {
-              inLink = false;
-              if (lastChildRightSpaceLineNumber) {
-                errors.push(lastChildRightSpaceLineNumber);
-              }
-            } else if (inLink) {
-              if ((index === 0) &&
-                  (child.content.trimLeft().length !== child.content.length)) {
-                errors.push(child.lineNumber);
-              }
-              lastChildRightSpaceLineNumber =
-                (child.content.trimRight().length !== child.content.length) ?
-                  child.lineNumber : 0;
-              index++;
+      filterTokens(params.tokens, "inline", function forToken(token) {
+        var inLink = false;
+        var index = 0;
+        var lastChildRightSpaceLineNumber = 0;
+        token.children.forEach(function forChild(child) {
+          if (child.type === "link_open") {
+            inLink = true;
+            index = 0;
+          } else if (child.type === "link_close") {
+            inLink = false;
+            if (lastChildRightSpaceLineNumber) {
+              errors.push(lastChildRightSpaceLineNumber);
             }
-          });
+          } else if (inLink) {
+            if ((index === 0) &&
+                (child.content.trimLeft().length !== child.content.length)) {
+              errors.push(child.lineNumber);
+            }
+            lastChildRightSpaceLineNumber =
+              (child.content.trimRight().length !== child.content.length) ?
+                child.lineNumber : 0;
+            index++;
+          }
         });
+      });
     }
   },
 
@@ -773,12 +763,11 @@ module.exports = [
     "desc": "Fenced code blocks should have a language specified",
     "tags": [ "code", "language" ],
     "func": function MD040(params, errors) {
-      filterTokens(params.tokens, "fence")
-        .forEach(function forToken(token) {
-          if (!token.info.trim()) {
-            errors.push(token.lineNumber);
-          }
-        });
+      filterTokens(params.tokens, "fence", function forToken(token) {
+        if (!token.info.trim()) {
+          errors.push(token.lineNumber);
+        }
+      });
     }
   }
 ];