Transition help for introductory code from Racket (DrScheme) and Python to Java Racket version 5.0.2 • set DrScheme to use the Advanced Student language for the examples in this guide, add these helper functions to the top of your program: !;;!displayln:!ANY!//>!VOID!!;;!will!act!similar!to!System.out.println!in!Java!!(define!(displayln!line)!!!(begin!(display!line)!!!!!!!!!!(newline)))!!;;!in/range!is!built/in!for!Racket,!but!not!the!ASL!teaching!language.!;;!in/range:!NaturalNumber!//>!(listof!NaturalNumber)!!;;!in/range!consumes!a!NaturalNumber!N!and!returns!a!list!!;;!counting!up!from!0!to!(N/1).!!(define!(in/range!x)!!!(build/list!x!identity))!!Python version 2.6.5 Java version 1.6.0_22 • since Java requires all code to belong to a class, and include a main method as the entry point to run code, all Java code snippets (unless otherwise stated) belong within the body of the main method. For example, the actual runnable code in Java for the first example would look like this: !public!class!Transition!{!!!public!static!void!main(String[]!args)!{!!!!!System.out.println(5!+!10);!!!}!}! Expression*Racket(DrScheme)!(displayln!(+!5!10))!Python!print!(5!+!10)!Java!System.out.println(5!+!10);! Definition/Variable*assignment*Racket(DrScheme)!(define!LBS_TO_KILO!#i0.45359237)!(displayln!(*!175!LBS_TO_KILO))!Python!LBS_TO_KILO!=!0.45359237!print!(175!*!LBS_TO_KILO)!Java!double!LBS_TO_KILO!=!0.45359237;!System.out.println(175!*!LBS_TO_KILO)!!Variable*re5assignment*(mutation)*Racket(DrScheme)!(define!age!19)!(displayln!age)!(set!!age!(+!age!1))!(displayln!age)!Python!age!=!19!print!age!age!=!age!+!1!print!age!Java!!int!age!=!19;!System.out.println(age);!age!=!age!+!1;!System.out.println(age);!//!ALTERNATIVE!1!int!age!=!19;!System.out.println(age);!age!+=!1;!System.out.println(age);!//!ALTERNATIVE!2!int!age!=!19;!System.out.println(age);!age++;!System.out.println(age);! Selection*(conditional)*Racket(DrScheme)!(define!JOE_AGE!25)!(cond!((<!JOE_AGE!18)!(displayln!"minor"))!!!!!!!!((<!JOE_AGE!65)!(displayln!"adult"))!!!!!!!!(else!(displayln!"senior")))!Python!JOE_AGE!=!25!if!JOE_AGE!<!18:!!!print!"minor"!elif!JOE_AGE!<!65:!!!print!"adult"!else:!!!print!"senior"!Java!int!JOE_AGE!=!25;!if!(JOE_AGE!<!18)!{!!!!!System.out.println("minor");!}!else!if!(JOE_AGE!<!65)!{!!!!!System.out.println("adult");!}!else!{!!!!!System.out.println("senior");!}!
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