List Manipulation

filter-atom

Description: Filters a list of atoms based on a predicate.

Parameters:

• List: The list of atoms to filter.

• Variable: The variable to use in the predicate.

• Filter: The predicate to apply (an expression that returns True or False).

Return: A new list containing only the atoms that satisfy the predicate.

Example:

!(filter-atom (1 2 3 4 5) $x (> $x 3)) ; Returns (4 5)

map-atom

Description: Applies a function to each atom in a list, creating a new list with the results.

Parameters:

• List: The list of atoms to map over.

• Variable: The variable to use in the mapping expression.

• Map: The expression to apply to each atom.

Return: A new list with the mapped values.

Example:

!(map-atom (1 2 3) $x (+ $x 1)) ; Returns (2 3 4)

foldl-atom

Description: Folds (reduces) a list of values into a single value, using a binary operation. This is a left fold.

Parameters:

• List: The list of values to fold.

• Init: The initial value.

• A: The variable to hold the accumulated value.

• B: The variable to hold the current element of the list.

• Op: The binary operation to apply (an expression using A and B).

Return: The final accumulated value.

Example:

!(foldl-atom (1 2 3 4) 0 $acc $x (+ $acc $x)) ; Returns 10 (1+2+3+4)

format-args

Description: Replace the ‘{}’ in the expression (the first argument) with an atom (the second atom).

Parameters:

• ExpressionAtom: Expression with {} to be replaced with the second parameter.

• Atom: Atom to replace {} in the expression.

Return: Expression with replaced {} with atoms

Example:

!(format-args (Probability of {} is {}%) (head 50)) ; Returns (Probability of head is 50%)