Update vimscript

vimscript.md

@@ -3,20 +3,276 @@ title: vimscript
 layout: default
 ---
 
+Variables
+---------
+
+```vim
+let var = "hello"
+```
+
+### Variable prefixes
+
+```vim
+let g:ack_options = '-s -H'    " g: global
+let s:ack_program = "ack"      " s: local to script
+let l:foo = 'bar'              " l: local to function
+let w:foo = 'bar'              " w: window
+let b:state = 'on'             " b: buffer
+let t:state = 'off'            " t: tab
+echo v:var                     " v: vim special
+
+let @/ = ""                    " @  register (this clears last search patterN)
+echo $PATH                     " $  env
+
+" they're actually a dictionary
+keys(s:)
+```
+
+### Vim options
+Prefix with `&`
+
+```vim
+echo "tabstop is " . &tabstop
+if &insertmode
+echo &g:option
+echo &l:option
+```
+
+### Operation assignment
+
+```vim
+let var -= 2
+let var += 5
+let var .= "string"   " concat
+```
+
+### Strings
+
+```vim
+let str = "String"
+let str = "String with \n newline"
+
+let literal = 'literal, no \ escaping'
+
+echo "result = " . re   " concatenation
+```
+
+```vim
+strlen(str)    " length
+strchars(str)  " character length
+```
+
+Functions
+---------
+
+```vim
+" prefix with s: for local script-only functions
+function! s:Initialize(cmd, args)
+  " a: prefix for arguments
+  echo "Command: " . a:cmd
+
+  return true
+endfunction
+```
+
+### Calling functions
+
+```vim
+call s:Initialize()
+call s:Initialize("hello")
+```
+
+### Consuming arguments
+
+```vim
+echo "Result: " . s:Initialize()
+```
+
+Commands
+--------
+
+```vim
+command! Save set fo=want tw=80 nowrap
+command! Save call s:Foo()
+```
+
+Flow
+----
+
+### Conditionals
+
+```vim
+let char = getchar()
+if char == "\<LeftMouse>"
+  " ...
+elseif char == "\<RightMouse>"
+  " ...
+else
+  " ...
+endif
+```
+
+### Boolean logic
+
+```vim
+if g:use_dispatch && s:has_dispatch
+endif
+```
+
+Lists
+-----
+
+```vim
+let mylist = [1, two, 3, "four"]
+
+let first = mylist[0]
+let last  = mylist[-1]
+
+" Supresses errors
+let second = get(mylist, 1)
+let second = get(mylist, 1, "NONE")
+
+len(mylist)
+empty(mylist)
+
+sort(list)
+let sortedlist = sort(copy(list))
+
+split('hello there world', ' ')
+```
+
+### Concatenation
+
+```vim
+let longlist = mylist + [5, 6]
+let mylist += [7, 8]
+```
+
+### Sublists
+
+```vim
+let shortlist = mylist[2:-1]
+let shortlist = mylist[2:]     " same
+
+let shortlist = mylist[2:2]    " one item
+```
+
+### Push
+
+```vim
+let alist = [1, 2, 3]
+let alist = add(alist, 4)
+```
+
+### Map
+
+```vim
+call map(files, "bufname(v:val)")  " use v:val for value
+call filter(files, 'v:val != ""')
+```
+
+Dictionaries
+------------
+
+```
+let colors = {
+  \ "apple": "red",
+  \ "banana": "yellow"
+}
+
+echo colors["a"]
+echo get(colors, "apple")   " supress error
+
+remove(colors, "apple")
+
+keys(dict)
+len(dict)
+```
+
+### Extending
+
+```
+" Extending with more
+let extend(s:fruits, { ... })
+```
+
+Casting
+-------
+
+```vim
+str2float("2.3")
+str2nr("3")
+float2nr("3.14")
+```
+
+Math
+----
+
+```vim
+sqrt(100)
+floor(3.5)
+ceil(3.3)
+abs(-3.4)
+
+sin() cos() tan()
+sinh() cosh() tanh()
+asin() acos() atan()
+```
+
+Vim-isms
+--------
+
+### Execute a command
+Runs an ex command you typically run with `:`
+
+execute "vsplit"
+execute "e " . fnameescape(filename)
+
+### Echo
+
+```
+echohl WarningMsg | echomsg "=> " . a:msg | echohl None
+```
+
+### Propmts
+
+```
+let result = confirm("Sure?")
+execute "confirm q"
+```
+
+### Built-ins
+
+```
+has("feature")  " :h feature-list
+executable("python")
+globpath(&rtp, "syntax/c.vim")
+
+exists("$ENV")
+exists(":command")
+exists("variable")
+exists("+option")
+exists("g:...")
+```
+
 Mapping
 -------
 
-    nnoremap
-    vmap
-    ...
+```
+nnoremap
+vmap
+...
+```
 
 Components:
 
-    [nvixso](nore)map
-     ^       ^
-     |       don't recurse
-     |
-     normal, visual, insert, eX mode, select, operator-pending
+```
+[nvixso](nore)map
+ ^       ^
+ |       don't recurse
+ |
+ normal, visual, insert, eX mode, select, operator-pending
+```
 
 Arguments:
 
@@ -24,69 +280,73 @@ Arguments:
 - `<silent>` - no echo
 - `<nowait>`
 
-Stuff
------
-
-    let var = "hello"
-    echo "var = " . var
-
-Functions
----------
-
-    has("feature")  " :h feature-list
-    executable("python")
-    globpath(&rtp, "syntax/c.vim")
-
-    if getchar() == "\<LeftMouse>"
-    endif
-
-    exe "vsplit"
-
 Syntax
 ------
 
 ### Highlights
 
-    hi Comment
-      term=bold,underline
-      gui=bold
-      ctermfg=4
-      guifg=#80a0ff
+```
+hi Comment
+  term=bold,underline
+  gui=bold
+  ctermfg=4
+  guifg=#80a0ff
+```
 
 ### Filetype detection
 
-    augroup filetypedetect
-      au! BufNewFile,BufRead *.json setf javascript
-    augroup END
+```
+augroup filetypedetect
+  au! BufNewFile,BufRead *.json setf javascript
+augroup END
 
-    au Filetype markdown setlocal spell
+au Filetype markdown setlocal spell
+```
 
 ### Conceal
 
-    set conceallevel=2
-    syn match newLine "<br>" conceal cchar=}
-    hi newLine guifg=green
+```
+set conceallevel=2
+syn match newLine "<br>" conceal cchar=}
+hi newLine guifg=green
+```
 
 ### Region conceal
 
-    syn region inBold concealends matchgroup=bTag start="<b>" end="</b>"
-    hi inBold gui=bold
-    hi bTag guifg=blue
+```
+syn region inBold concealends matchgroup=bTag start="<b>" end="</b>"
+hi inBold gui=bold
+hi bTag guifg=blue
+```
 
 ### Syntax
 
-    syn match :name ":regex" :flags
+```
+syn match :name ":regex" :flags
 
-    syn region Comment  start="/\*"  end="\*/"
-    syn region String   start=+"+    end=+"+	 skip=+\\"+
+syn region Comment  start="/\*"  end="\*/"
+syn region String   start=+"+    end=+"+	 skip=+\\"+
 
-    syn cluster :name contains=:n1,:n2,:n3...
+syn cluster :name contains=:n1,:n2,:n3...
 
-    flags:
-      keepend
-      oneline
-      nextgroup=
-      contains=
-      contained
+flags:
+  keepend
+  oneline
+  nextgroup=
+  contains=
+  contained
 
-    hi def link markdownH1 htmlH1
+hi def link markdownH1 htmlH1
+```
+
+### Include guards
+
+```
+if exists('g:loaded_myplugin')
+  finish
+endif
+
+" ...
+
+let g:loaded_myplugin = 1
+```