Master programming syntax, solve interactive challenges & run live code in Syntaxis Explore Arena →
menu_book Course Curriculum (Racket) expand_more
Racket / Contracts and Modules

define/contract

Learn define/contract in Racket with a construct-specific explanation, unique example, engineering boundary, and mastery check.

10 min read • Intermediate

define/contract is a focused Racket topic inside Contracts and Modules. This lesson explains the construct itself, the state or value it operates on, and the observable result it produces.

Read the example as a small executable experiment. Identify the exact syntax that belongs to define/contract, then change one input and predict the result before running it.

Topic-specific example

racket-06-02-define-contract.rkt
racket Try It Live
(define/contract (half x) (-> real? real?) (/ x 2.0))
(half 9)
Edge case / engineering note

define/contract has rules that are easy to miss when the example is copied mechanically. Check the feature-specific boundary shown by this construct: scope, mutability, evaluation order, type constraints, lifetime, error behavior, compile-time restrictions, or resource cleanup where applicable.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content