Add Multi-Argument Functions As Syntactic Sugar as a reasonml til

README.md

@@ -10,7 +10,7 @@ smart people at [Hashrocket](http://hashrocket.com/).
 For a steady stream of TILs from a variety of rocketeers, checkout
 [til.hashrocket.com](https://til.hashrocket.com/).
 
-_613 TILs and counting..._
+_614 TILs and counting..._
 
 ---
 
@@ -441,6 +441,7 @@ _613 TILs and counting..._
 ### ReasonML
 
 - [Exhaustive Pattern Matching Of List Variants](reason/exhaustive-pattern-matching-of-list-variants.md)
+- [Multi-Argument Functions As Syntactic Sugar](reason/multi-argument-functions-as-syntactic-sugar.md)
 - [Pattern Match On Exceptions](reason/pattern-match-on-exceptions.md)
 - [String Interpolation With Integers And Sprintf](reason/string-interpolation-with-integers-and-sprintf.md)
 

reason/multi-argument-functions-as-syntactic-sugar.md

@@ -0,0 +1,33 @@
+# Multi-Argument Functions As Syntactic Sugar
+
+When writing a multi-argument function, like the following `adder` function:
+
+```reason
+let adder = (x, y) => x + y;
+
+adder(2, 3); /* => 5 */
+```
+
+We are utilizing a syntactic sugar of the function syntax. The same function
+can be written as such:
+
+```reason
+let adder = (x) => (y) => x + y;
+
+adder(2, 3); /* => 5 */
+```
+
+As you can see, we can apply the function in the same way.
+
+This is useful because it means we can partially apply (or _curry_) our
+functions to create other functions.
+
+```reason
+let adder = (x, y) => x + y;
+let twoAdder = adder(2);
+
+twoAdder(5); /* => 7 */
+```
+
+[source
+code](https://reasonml.github.io/en/try.html?reason=DYUwLgBAhgJjICcIF4IAoAeBKFA+dAnjsvhhANQQEDcAULQFIDOAdMAPYDmas8CaAFgA0EAKxYsdWqEhgA7uwCCcRCmgr+AJkn1mbLmnlKNacZKA)