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Vimprint - A Vim Keystroke Parser
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nelstrom
May 28, 2013
Technology
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Vimprint - A Vim Keystroke Parser
nelstrom
May 28, 2013
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Transcript
VIMPRINT A VIM KEYSTROKE PARSER 28th May, 2013 Drew Neil
@nelstrom
VIMPRINT should... visualize keystrokes in realtime
VIMPRINT should... understand all built-in commands
VIMPRINT should... be extensible
VimSpeak Turns spoken English into keystrokes https://github.com/AshleyF/VimSpeak
None
VimSplain Turns keystrokes into plain English https://github.com/pafcu/Vimsplain
Vimulator Turns live keystrokes into plain English https://github.com/thoughtbot/vimulator
None
VimGolf Logs real keystrokes https://github.com/igrigorik/vimgolf
None
vim -w keystrokes are BUFFERED
None
Parslet 1st attempt at parsing Vim keystrokes
None
class Vimprint < Parslet::Parser rule(:start) { match('[iIaAoOsS]').as(:switch) } rule(:typing) {
match('[^\e]').repeat.as(:typing) } rule(:terminate) { match('\e').as(:escape) } rule(:insertion) { start >> typing >> terminate } root(:insertion) end
gv major stumbling block: switch from Normal mode to Visual
mode and select the last selected text
Ragel 2nd attempt at parsing Vim keystrokes
Ragel state machines can not only recognize byte sequences as
regular expression machines do, but can also execute code at arbitrary points in the recognition of a regular language.
%%{ machine vim_print; action return { fret; } action push_insert_mode
{ fcall insert_mode; } escape = 27; input = (any - escape); motion = [hjklbwe0]; switch = [iIaAsSoO]; insert_mode := ( input* escape @return ); normal_mode := ( motion | switch @push_insert_mode )*; }%%
2 IN 1 insert_mode normal_mode '0', 'b', 'e', 'h', 'j'..'l',
'w' 'A', 'I', 'O', 'S', 'a', 'i', 'o', 's' / push_insert_mode 3 27 / return DEF
action H { @head = p } action T {
@tail = p } action EmitMotion { @events << {motion: strokes} } action EmitSwitch { @events << {switch: strokes} } action EmitInput { @events << {input: strokes} } action EmitEscape { @events << {escape: '<Esc>'} } escape = 27 >H@T @EmitEscape; input = (any - escape) >H@T @EmitInput; motion = [hjklbwe0] >H@T @EmitMotion; switch = [iIaAsSoO] >H@T @EmitSwitch;
class VimParser attr_accessor :head, :tail, :data def initialize(listener) @events =
listener %% write data; end def process(input) @data = input.unpack("c*") eof = @data.length stack = [] %% write init; %% write exec; end def strokes @data[@head..@tail].pack('c*') end end
VimParser.new(recorder = []).process("helihello\e") puts recorder {:motion=>"h"} {:motion=>"e"} {:motion=>"l"} {:switch=>"i"} {:input=>"h"}
{:input=>"e"} {:input=>"l"} {:input=>"l"} {:input=>"o"} {:escape=>"<Esc>"} https://gist.github.com/nelstrom/5663083
FATAL FLAWS with parsing keystrokes
FATAL FLAWS no timestamps <leader>{...}
FATAL FLAWS no document context :s/{pattern}/{string}/c
FATAL FLAWS no filetype detection
HALP! https://github.com/nelstrom/vimprint Vimprint Realtime Vim keystroke visualizer