As shown in the image, I was just reminded that you can run
javap inside the Scala REPL. The REPL help command shows some other things you can do:
scala> :help All commands can be abbreviated, e.g., :he instead of :help. :edit <id>|<line> edit history :help [command] print this summary or command-specific help :history [num] show the history (optional num is commands to show) :h? <string> search the history :imports [name name ...] show import history, identifying sources of names :implicits [-v] show the implicits in scope :javap <path|class> disassemble a file or class name :line <id>|<line> place line(s) at the end of history :load <path> interpret lines in a file :paste [-raw] [path] enter paste mode or paste a file :power enable power user mode :quit exit the interpreter :replay [options] reset the repl and replay all previous commands :require <path> add a jar to the classpath :reset [options] reset the repl to its initial state, forgetting all session entries :save <path> save replayable session to a file :sh <command line> run a shell command (result is implicitly => List[String]) :settings <options> update compiler options, if possible; see reset :silent disable/enable automatic printing of results :type [-v] <expr> display the type of an expression without evaluating it :kind [-v] <type> display the kind of a type. see also :help kind :warnings show the suppressed warnings from the most recent line which had any
Way back in the 1990s I created some “cheat sheets” for Unix training classes that I taught. Somewhere in the 2000s I updated them to make sure they worked with Linux as well, Here then are two Unix/Linux cheat sheets I created (way back when) that you can print out if you’re just learning Linux and the vi/vim editor:
This article titled, Little things I like to do with git, has a fun series of git commands.
A flowchart on how to undo changes in Git, from this tweet.
Mac OS X performance tuning tools and commands. From this tweet by Brendan Gregg.
It took me a few minutes to figure out that when you want help on Play Framework console commands (i.e., the Play command line tool), you may get more useful help by typing
help play instead of just
help. Using the first command shows information on commands like
console, etc., which is what I'm more interested in.
To take a quick look at this, here's what you get when you type
I just started using tmux last week, and created a cheat sheet to help me remember the basic
tmux commands, and I thought I'd share that here.
The cheat sheet has a few things that are specific to my configuration file, so to begin with, here is my ~/.tmux.conf file: