Operations

Operations are used to process and transform data in Wolf.

Applying a function

Wolf allows you to apply functions to a single tuple of data at a time. This is done by prefixing the tuple with the function name.

-- Negates 2.
negate [2]

The tuple can contain multiple data.

-- Adds 9 and 10.
add [9, 10]

Blocks

Blocks are declared with parentheses ().

They can be included in other expressions; the contents of the block are evaluated independently of the other expression, meaning they can change the order in which operations are done.

-- The block evaluates to 8, then is multiplied by 2.
2 * (5 + 3)

Other kinds of block will be introduced later.

Special notation

Certain functions in Wolf are important enough to have special notation.

-- Standard arithmetic (including exponentiation).
2/5 + 4*3 - 6^4

-- Negation and double negation.
-2 * +6

-- Floor division and floor modulo.
4 // 3 % 5

-- Ceiling division.
4 /^ 3

-- Equality comparisons.
1 + 1 == 4 - 2 == 2

-- Equality comparisons and boolean combination.
9 == 9 and 10 == 10 or 19 != 21

-- Single-ended ranges.
(2 < 5) and (3 <= 3) or (4 > 5) and (6 >= 0)

-- Double-ended ranges (combines single-ended ranges).
(0 <= 5 < 21) or (20 >= 5 > -1)

The table below shows these operators and how they relate to each other. Higher priority operators are evaluated before lower priority operators in an expression.

Other non-operators are also included to complete the comparison.

---

Syntax	Function	Priority	Notes
A [B]	(function evaluation)	▲ ▲ ▲ ▲ ▲
A.B	(accessing named data)	▲ ▲ ▲ ▲
!A	invert A	▲ ▲ ▲	Pick one1
-A	negate A	▲ ▲ ▲	Pick one1
+A	double_negate A	▲ ▲ ▲	Pick one1
#A	count A	▲ ▲ ▲	Pick one1
A ^ B	exponent [A, B, ...]	▲ ▲
A * B	multiply [A, B, ...]	▲
A / B	divide [A, B, ...]	▲
A // B	floor_divide [A, B, ...]	▲
A /^ B	ceil_divide [A, B, ...]	▲
A % B	floor_mod [A, B, ...]	▲
A + B	add [A, B, ...]
A - B	subtract [A, B, ...]
A < B	less_than [A, B]	▼	Must form an order2
A > B	more_than [A, B]	▼	Must form an order2
A <= B	less_or_equals [A, B]	▼	Must form an order2
A >= B	more_or_equals [A, B]	▼	Must form an order2
A == B	equals [A, B, ...]	▼ ▼
A != B	invert_equals [A, B, ...]	▼ ▼
A and B	and_values [A, B, ...]	▼ ▼ ▼
A or B	or_values [A, B, ...]	▼ ▼ ▼ ▼
A -> B	(manual chaining)	▼ ▼ ▼ ▼ ▼
A => B	(automatic chaining)	▼ ▼ ▼ ▼ ▼

Integer conversion

Wolf does not implicitly convert between num and int. Instead, the arithmetic operators accept any mix of int or num, and return int if the types guarantee the result is an integer.

That means:

• / always returns num, because not all integers divide evenly.
• // and /^ always returns int, because the result is floored.
• All other operators return int if all operands are int.

You can use this behaviour to explicitly convert between num and int:

-- Converts the integer to the nearest floating-point number.
2 / 1
-- Floors the floating-point number towards the largest integer less than it.
2.4 // 1
-- Floors the floating-point number towards the smallest integer greater than it.
2.4 /^ 1

Note that num and int may handle overflow, underflow, and division by zero differently to each other.

1. Unary operators cannot be mixed. ↩ ↩² ↩³ ↩⁴

2. < / <= cannot be mixed with > / >= at the same level. ↩ ↩² ↩³ ↩⁴