Flow Control

Reflex has the standard flow control statements such as if ... else , while , for loops.

If

The Reflex if statement has the following form:

if booleanExpression do
   block
else do
   block
end

For statements without an else block the complete else do block can be omitted.

// An If statement
a = 4;
b = 2;
if a > 3 do
   println("A is greater than 3");
else do 
   println("A is less than or equal to 3");
end

if b == 2 do
   println("Yes, b is 2");
end

Note that there does not need to be a semi-colon after the end keyword here.

While

The Reflex while statement has the following form:

while booleanExpression do
    block
end

And an example:

// A while loop
a = true;
b = 0;
while a do
   b = b + 1;
    if b > 5 do
        a = false;
    end
end

For

Reflex has two different for loop forms. The first, the counting form, assigns a numeric variable the values from a starting number to an ending number (inclusive) and calls the inner block for each iteration.

// A for loop
for a = 0 to 10 do
   println("The value of a is " + a);
end

The second is known as the iterator form, and it takes as a secondary argument a list expression (which can be a variable or an expression that yields a list). The value of the variable is set to each element in the list and the inner block is called with that element set.

// A for loop
a = [1, 2, 3, 4 ];
b = [];
for c in a do
   b = b + ( c * 2 );
end
assert(c == [2, 4, 6, 8 ];

Break and Continue

Reflex also supports break and continue semantics, which work as expected. The following code snippets (which assert correctly) show this behavior.

res = [];

for i = 0 to 10 do
   res = res + i;
   if i == 5 do
     break;
   end
end

assert(res == [0,1,2,3,4,5]);

and a continue example:

res = [];
for i = 0 to 10 do
    if i < 5 do
       continue;
    end
    res = res + i;
end

assert(res == [5,6,7,8,9,10]);

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