From 52b5916518c286677e234d0bb1bad3a57b05fc23 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?M=C3=A1rton=20Boros?= <martonboros@gmail.com>
Date: Sun, 22 Mar 2015 04:45:42 +0100
Subject: [PATCH 1/2] improve Unsafe

---
 README.md                   | 14 ++++++++++++--
 src/Data/String/Unsafe.purs | 26 +++++++++++++++++++++++---
 2 files changed, 35 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index 31504b7..3cbbacc 100644
--- a/README.md
+++ b/README.md
@@ -434,7 +434,7 @@ charCodeAt :: Number -> String -> Number
 
 Returns the numeric Unicode value of the character at the given index.
 
-**Unsafe:** returns `NaN` if the index is out of bounds.
+**Unsafe:** throws runtime exception if the index is out of bounds.
 
 #### `charAt`
 
@@ -444,7 +444,17 @@ charAt :: Number -> String -> Char
 
 Returns the character at the given index.
 
-**Unsafe:** returns an illegal value if the index is out of bounds.
+**Unsafe:** throws runtime exception if the index is out of bounds.
+
+#### `char`
+
+``` purescript
+char :: String -> Char
+```
+
+Converts a string of length `1` to a character..
+
+**Unsafe:** throws runtime exception if length is not `1`.
 
 
 
diff --git a/src/Data/String/Unsafe.purs b/src/Data/String/Unsafe.purs
index c31cba7..18f6bd4 100644
--- a/src/Data/String/Unsafe.purs
+++ b/src/Data/String/Unsafe.purs
@@ -1,6 +1,7 @@
 -- | Unsafe string and character functions.
 module Data.String.Unsafe
-  ( charAt
+  ( char
+  , charAt
   , charCodeAt
   ) where
 
@@ -8,11 +9,14 @@ module Data.String.Unsafe
 
   -- | Returns the numeric Unicode value of the character at the given index.
   -- |
-  -- | **Unsafe:** returns `NaN` if the index is out of bounds.
+  -- | **Unsafe:** throws runtime exception if the index is out of bounds.
   foreign import charCodeAt
     """
     function charCodeAt(i) {
       return function(s) {
+        if (s.length <= i) {
+          throw new Error("Data.String.Unsafe.charCodeAt: Invalid index.");
+        };
         return s.charCodeAt(i);
       };
     }
@@ -20,12 +24,28 @@ module Data.String.Unsafe
 
   -- | Returns the character at the given index.
   -- |
-  -- | **Unsafe:** returns an illegal value if the index is out of bounds.
+  -- | **Unsafe:** throws runtime exception if the index is out of bounds.
   foreign import charAt
     """
     function charAt(i) {
       return function(s) {
+        if (s.length <= i) {
+          throw new Error("Data.String.Unsafe.charAt: Invalid index.");
+        };
         return s.charAt(i);
       };
     }
     """ :: Number -> String -> Char
+
+  -- | Converts a string of length `1` to a character..
+  -- |
+  -- | **Unsafe:** throws runtime exception if length is not `1`.
+  foreign import char
+    """
+    function $$char(s) {
+      if (s.length != 1) {
+        throw new Error("Data.String.Unsafe.char: Expected string of length 1.");
+      };
+      return s.charAt(0);
+    }
+    """ :: String -> Char

From 7445c05bd0466173961361a008e48e7659cc5897 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?M=C3=A1rton=20Boros?= <martonboros@gmail.com>
Date: Sun, 22 Mar 2015 06:34:55 +0100
Subject: [PATCH 2/2] fix typo

---
 README.md                   | 2 +-
 src/Data/String/Unsafe.purs | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 3cbbacc..4545e05 100644
--- a/README.md
+++ b/README.md
@@ -452,7 +452,7 @@ Returns the character at the given index.
 char :: String -> Char
 ```
 
-Converts a string of length `1` to a character..
+Converts a string of length `1` to a character.
 
 **Unsafe:** throws runtime exception if length is not `1`.
 
diff --git a/src/Data/String/Unsafe.purs b/src/Data/String/Unsafe.purs
index 18f6bd4..547f002 100644
--- a/src/Data/String/Unsafe.purs
+++ b/src/Data/String/Unsafe.purs
@@ -37,7 +37,7 @@ module Data.String.Unsafe
     }
     """ :: Number -> String -> Char
 
-  -- | Converts a string of length `1` to a character..
+  -- | Converts a string of length `1` to a character.
   -- |
   -- | **Unsafe:** throws runtime exception if length is not `1`.
   foreign import char