gistfile1.txt

Say that /tmp/ex.rkt is

#lang racket
(define x 42)
x

Now:

$ racket
Welcome to Racket v6.10.
> ,h
,h
; Available commands:
;   help (h ?): display available commands
;   exit (quit ex): exit racket
;   cd: change the current directory
;   pwd: display the current directory
;   shell (sh ls cp mv rm md rd git svn): run a shell command
;   edit (e): edit files in your $EDITOR
;   drracket (dr drr): edit files in DrRacket
;   apropos (ap): look for a binding
;   describe (desc id): describe a (bound) identifier
;   doc: browse the racket documentation
;   require (req r): require a module
;   require-reloadable (reqr rr): require a module, make it reloadable
;   enter (en): require a module and go into its namespace
;   toplevel (top): go back to the toplevel
;   load (ld): load a file
;   backtrace (bt): see a backtrace of the last exception
;   time: time an expression
;   trace (tr): trace a function
;   untrace (untr): untrace a function
;   errortrace (errt inst): errortrace instrumentation control
;   profile (prof): profiler control
;   execution-counts: execution counts
;   coverage (cover): coverage information via a sandbox
;   switch-namespace (switch): switch to a different repl namespace
;   syntax (stx st): set syntax object to inspect, and control it
;   check-requires (ckreq): check the `require's of a module
;   log: control log output
;   install!: install xrepl in your Racket init file
> ,en /tmp/ex.rkt
,en /tmp/ex.rkt
42
"/tmp/ex.rkt"> x
x
42

Now edit ex.rkt to change x to 999 and save the file. Then:


"/tmp/ex.rkt"> ,en /tmp/ex.rkt
,en /tmp/ex.rkt
  [re-loading /tmp/ex.rkt]
999
"/tmp/ex.rkt"> x
x
999
"/tmp/ex.rkt">