Implemented math @round

asteroid/modules/math.ast

@@ -165,6 +165,21 @@ __retval__ = ('integer', math.floor(val_x[1]))
 "
 end
 
+------------------------------------------------------------------
+function round
+------------------------------------------------------------------
+-- Return x rounded to the nearest integer. If two integers are equally close,
+-- x is rounded to the nearest even integer.
+with (x:%real) do return escape
+"
+global __retval__
+
+val_x = state.symbol_table.lookup_sym('x')
+
+__retval__ = ('integer', round(val_x[1]))
+"
+end
+
 ------------------------------------------------------------------
 function gcd
 ------------------------------------------------------------------

asteroid/test-suites/regression-tests/test147.ast

@@ -0,0 +1,29 @@
+load system math.
+
+let test_cases = [
+    (3.14, 3),
+    (3.508, 4),
+    (12.99999, 13),
+    (13.00000, 13),
+    (13.00001, 13),
+    (13.49999, 13),
+    (13.50000, 14),
+    (13.50001, 14),
+    (13.99999, 14),
+    (14.00000, 14),
+    (14.00001, 14),
+    (14.49999, 14),
+    (14.50000, 14),
+    (12.5, 12),
+    (13.5, 14),
+    (14.5, 14),
+    (15.5, 16),
+    (0.0, 0),
+    (-0.0, 0),
+    (-53.246, -53),
+    (-53.5, -54)
+].
+
+for (input, expected_output) in test_cases do
+    assert (math @round input == expected_output).
+end

docs/Reference Guide.rst

@@ -1187,6 +1187,10 @@ math **@ceil** x:%real
 math **@floor** x:%real
       Returns the floor of x: the largest integer less than or equal to x.
 
+math **@round** x:%real
+      Returns x rounded to the nearest integer. If two integers are equally
+      close, x is rounded to the nearest even integer.
+
 math **@gcd** (a:%integer, b:%integer)
       Returns the greatest common denominator that both integers share.
 

docs/Reference Guide.txt

@@ -1044,6 +1044,10 @@ math **@ceil** x:%real
 math **@floor** x:%real
       Returns the floor of x: the largest integer less than or equal to x.
 
+math **@round** x:%real
+      Returns x rounded to the nearest integer. If two integers are equally
+      close, x is rounded to the nearest even integer.
+
 math **@gcd** (a:%integer, b:%integer)
       Returns the greatest common denominator that both integers share.