CSC104H1 Chapter Notes - Chapter 1: Racket (Programming Language)
Document Summary
Expression: all the stuff you"ve typed (from the left parenthesis through the matching right parenthesis) Functions/ operations/ procedures: such as rotate-cw, rotate-ccw, and rotate-180, which, given a picture, produce a different picture. Argument to the function: the picture you give them to work on. Value of the expression: the new picture you see as a result of applying the function to the argument. First step: > (require picturing-programs: flip-vertical / flip-horizontal. Syntax rule 0: to do something to one or more images, type a left- parenthesis, the name of the operation you want to do, then the image(s) you want to do it to, then a right-parenthesis. Note that beside, above, and overlay are functions too, just like flip- vertical, rotate-ccw, etc. , but they work on two or more arguments rather than one; they wouldn"t make sense applied to only one picture. Identifier can be made up of letters, numerals, and punctuation marks.
