scheme and if condition

if-statement, scheme

Solution

From R5RS:

syntax: `(if test consequent alternate)`

syntax: `(if test consequent)`

Semantics: An `if` expression is evaluated as follows: first, test is evaluated. If it yields a true value (see section 6.3.1), then consequent is evaluated and its value(s) is(are) returned. Otherwise alternate is evaluated and its value(s) is(are) returned. If test yields a false value and no alternate is specified, then the result of the expression is unspecified.

So your `if` expression becomes:

(if x y)

Problem

I want to return nothing when if condition is not met, for instance ``` (if x y z) ``` so if x is not met, z will be executed and I want to do nothing at z, just same as pythons "pass"

Original source