Show prompt on same line

src/eval.rs

@@ -1,4 +1,5 @@
 use std::io;
+use std::io::Write;
 
 pub fn do_math(arguments: String, operator: char) -> u32 {
     let split_args = arguments.split("-").collect::<Vec<&str>>();
@@ -38,7 +39,8 @@ pub fn args_or_comments(arguments: &str) -> String {
 }
 
 pub fn read_stdin(prompt: &str) -> String {
-    println!("{}", prompt);
+    print!("{}", prompt);
+    io::stdout().flush().unwrap();
 
     let mut result = String::new();
     io::stdin().read_line(&mut result).expect("Expected a string!");