[[ Bug 20079 ]] Add square root operator to math lib

montegoulding · montegoulding · commit d7b3ceba3f44 · 2017-07-13T21:33:52.000+10:00
diff --git a/docs/notes/bugfix-20079.md b/docs/notes/bugfix-20079.md
@@ -0,0 +1 @@
+# Add `the square root of <number>` to the math library
diff --git a/libscript/src/math.lcb b/libscript/src/math.lcb
@@ -76,6 +76,9 @@ public foreign handler MCMathEvalMaxNumber(in Left as Number, in Right as Number
 
 public foreign handler MCMathEvalRandomReal(out Value as CDouble) returns nothing binds to "<builtin>"
 
+public foreign handler MCMathEvalSqrtReal(in Operand as CDouble, out Value as CDouble) returns nothing binds to "<builtin>"
+public foreign handler MCMathEvalSqrtNumber(in Operand as Number, out Value as Number) returns nothing binds to "<builtin>"
+
 public foreign handler MCMathEvalConvertBase(in Operand as String, in Source as LCInt, in Target as LCInt, out Value as String) returns nothing binds to "<builtin>"
 public foreign handler MCMathEvalConvertToBase10(in Operand as String, in Source as LCInt, out Value as LCInt) returns nothing binds to "<builtin>"
 public foreign handler MCMathEvalConvertFromBase10(in Operand as LCInt, in Target as LCInt, out Value as String) returns nothing binds to "<builtin>"
@@ -565,6 +568,42 @@ end syntax
 
 --
 
+/**
+Syntax:		sqrt(<Operand>)
+Summary:    Square root operator.
+Operand:    An expression that evaluates to a number.
+
+Example:
+variable tVar as Number
+put sqrt(9) into tVar -- tVar contains 3
+
+Example:
+variable tVar as Number
+put the square root of 4 into tVar -- tVar contains 2
+
+Description:
+The square root of a number is the number which must be
+squared to obtain number : sqrt(number)^2 is equal to number.
+
+Tags: Math
+*/
+
+syntax SquareRootOperator is prefix operator with function chunk precedence
+    "the" "square" "root" "of" <Operand: Expression>
+begin
+    MCMathEvalSqrtNumber(Operand, output)
+end syntax
+
+public handler Sqrt(in pOperand as Number) returns Number
+    variable tVar as Number
+    unsafe
+        MCMathEvalSqrtNumber(pOperand, tVar)
+    end unsafe
+    return tVar
+end handler
+
+--
+
 /**
 Summary:    Converts the base of <Operand>
 Operand:    An expression that evaluates to a string.
diff --git a/libscript/src/module-math.cpp b/libscript/src/module-math.cpp
@@ -407,6 +407,22 @@ extern "C" MC_DLLEXPORT_DEF void MCMathEvalRandomReal(double& r_output)
     r_output = MCSRandomReal();
 }
 
+extern "C" MC_DLLEXPORT_DEF void MCMathEvalSqrtReal(double p_operand, double& r_output)
+{
+    r_output = sqrt(p_operand);
+}
+
+extern "C" MC_DLLEXPORT_DEF void MCMathEvalSqrtNumber(MCNumberRef p_operand, MCNumberRef& r_output)
+{
+    double t_operand;
+    t_operand = MCNumberFetchAsReal(p_operand);
+    
+    double t_result;
+    MCMathEvalSqrtReal(t_operand, t_result);
+    
+    MCNumberCreateWithReal(t_result, r_output);
+}
+
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 
 extern "C" MC_DLLEXPORT_DEF void MCMathEvalConvertToBase10(MCStringRef p_operand, integer_t p_source_base, integer_t& r_output)

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	+# Add `the square root of <number>` to the math library