Noticed repeated typos in docs and comments

Closes #10471.

PiperOrigin-RevId: 287827212
diff --git a/site/docs/configurable-attributes.md b/site/docs/configurable-attributes.md
index 93e0a0c..2c74ca8 100644
--- a/site/docs/configurable-attributes.md
+++ b/site/docs/configurable-attributes.md
@@ -847,7 +847,7 @@
 ## <a name="boolean-select"></a>Why does select() always return true?
 Because *macros* (but not rules) by definition
 [can't evaluate select(s)](#macros-select), any attempt to do so
-usually produces a an error:
+usually produces an error:
 
 ```sh
 ERROR: /myworkspace/myproject/BUILD:17:1: Traceback
diff --git a/src/main/java/com/google/devtools/build/lib/rules/apple/AvailableXcodesRule.java b/src/main/java/com/google/devtools/build/lib/rules/apple/AvailableXcodesRule.java
index 8cffafe..a545ad0 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/apple/AvailableXcodesRule.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/apple/AvailableXcodesRule.java
@@ -69,6 +69,6 @@
 
 <p>Two targets of this rule can be depended on by an <code>xcode_config</code> rule instance to
 indicate the remotely and locally avaialable xcode versions.
-This allows selection of a an official xcode version from the collectively avaialble xcodes.</p>
+This allows selection of an official xcode version from the collectively avaialble xcodes.</p>
 
 <!-- #END_BLAZE_RULE -->*/
diff --git a/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeConfigRule.java b/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeConfigRule.java
index 85c8649..ee70f0f 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeConfigRule.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/apple/XcodeConfigRule.java
@@ -101,6 +101,6 @@
 
 <p>A single target of this rule can be referenced by the <code>--xcode_version_config</code> build
 flag to translate the <code>--xcode_version</code> flag into an accepted official xcode version.
-This allows selection of a an official xcode version from a number of registered aliases.</p>
+This allows selection of an official xcode version from a number of registered aliases.</p>
 
 <!-- #END_BLAZE_RULE -->*/