if

Ol provides extended syntax for if statement.

This is classic R⁷RS if statement:

• (if <expression> <then-clause>)
• (if <expression> (begin <then1-clause> .. <thenN-clause>))
• (if <expression> <then-clause> <else-clause>)
• (if <expression> <then-clause> (begin <else1-clause> .. <elseN-clause>))
• (if <expression> (begin <then1-clause> .. <thenN-clause>) (begin <else1-clause> .. <elseN-clause>))

Ol provides special words then and else and extends if statement as:

• (if <expression> then <then-clause>)
• (if <expression> then <then1-clause> .. <thenN-clause>)
• (if <expression> <then-clause> else <else-clause>)
• (if <expression> <then-clause> else <else1-clause> .. <elseN-clause>)
• (if <expression> then <then-clause> else <else-clause>)
• (if <expression> then <then-clause> else <else1-clause> .. <elseN-clause>)
• (if <expression> then <then1-clause> .. <thenN-clause> else <else-clause>)
• (if <expression> then <then1-clause> .. <thenN-clause> else <else1-clause> .. <elseN-clause>)

As you can see no more begin is required if you use then or else. Your code is now became more human readable:

(if some-expression
  then please-do-something
       and-do-more-something
  else do-something-more)