1" Vim script to work like "less"
2" Maintainer:	Bram Moolenaar <Bram@vim.org>
3" Last Change:	2006 Dec 05
4
5" Avoid loading this file twice, allow the user to define his own script.
6if exists("loaded_less")
7  finish
8endif
9let loaded_less = 1
10
11" If not reading from stdin, skip files that can't be read.
12" Exit if there is no file at all.
13if argc() > 0
14  let s:i = 0
15  while 1
16    if filereadable(argv(s:i))
17      if s:i != 0
18	sleep 3
19      endif
20      break
21    endif
22    if isdirectory(argv(s:i))
23      echomsg "Skipping directory " . argv(s:i)
24    elseif getftime(argv(s:i)) < 0
25      echomsg "Skipping non-existing file " . argv(s:i)
26    else
27      echomsg "Skipping unreadable file " . argv(s:i)
28    endif
29    echo "\n"
30    let s:i = s:i + 1
31    if s:i == argc()
32      quit
33    endif
34    next
35  endwhile
36endif
37
38set nocp
39syntax on
40set so=0
41set hlsearch
42set incsearch
43nohlsearch
44" Don't remember file names and positions
45set viminfo=
46set nows
47" Inhibit screen updates while searching
48let s:lz = &lz
49set lz
50
51" Used after each command: put cursor at end and display position
52if &wrap
53  noremap <SID>L L0:redraw<CR>:file<CR>
54  au VimEnter * normal! L0
55else
56  noremap <SID>L Lg0:redraw<CR>:file<CR>
57  au VimEnter * normal! Lg0
58endif
59
60" When reading from stdin don't consider the file modified.
61au VimEnter * set nomod
62
63" Can't modify the text
64set noma
65
66" Give help
67noremap h :call <SID>Help()<CR>
68map H h
69fun! s:Help()
70  echo "<Space>   One page forward          b         One page backward"
71  echo "d         Half a page forward       u         Half a page backward"
72  echo "<Enter>   One line forward          k         One line backward"
73  echo "G         End of file               g         Start of file"
74  echo "N%        percentage in file"
75  echo "\n"
76  echo "/pattern  Search for pattern        ?pattern  Search backward for pattern"
77  echo "n         next pattern match        N         Previous pattern match"
78  echo "\n"
79  echo ":n<Enter> Next file                 :p<Enter> Previous file"
80  echo "\n"
81  echo "q         Quit                      v         Edit file"
82  let i = input("Hit Enter to continue")
83endfun
84
85" Scroll one page forward
86noremap <script> <Space> :call <SID>NextPage()<CR><SID>L
87map <C-V> <Space>
88map f <Space>
89map <C-F> <Space>
90map z <Space>
91map <Esc><Space> <Space>
92fun! s:NextPage()
93  if line(".") == line("$")
94    if argidx() + 1 >= argc()
95      quit
96    endif
97    next
98    1
99  else
100    exe "normal! \<C-F>"
101  endif
102endfun
103
104" Re-read file and page forward "tail -f"
105map F :e<CR>G<SID>L:sleep 1<CR>F
106
107" Scroll half a page forward
108noremap <script> d <C-D><SID>L
109map <C-D> d
110
111" Scroll one line forward
112noremap <script> <CR> <C-E><SID>L
113map <C-N> <CR>
114map e <CR>
115map <C-E> <CR>
116map j <CR>
117map <C-J> <CR>
118
119" Scroll one page backward
120noremap <script> b <C-B><SID>L
121map <C-B> b
122map w b
123map <Esc>v b
124
125" Scroll half a page backward
126noremap <script> u <C-U><SID>L
127noremap <script> <C-U> <C-U><SID>L
128
129" Scroll one line backward
130noremap <script> k <C-Y><SID>L
131map y k
132map <C-Y> k
133map <C-P> k
134map <C-K> k
135
136" Redraw
137noremap <script> r <C-L><SID>L
138noremap <script> <C-R> <C-L><SID>L
139noremap <script> R <C-L><SID>L
140
141" Start of file
142noremap <script> g gg<SID>L
143map < g
144map <Esc>< g
145
146" End of file
147noremap <script> G G<SID>L
148map > G
149map <Esc>> G
150
151" Go to percentage
152noremap <script> % %<SID>L
153map p %
154
155" Search
156noremap <script> / H$:call <SID>Forward()<CR>/
157if &wrap
158  noremap <script> ? H0:call <SID>Backward()<CR>?
159else
160  noremap <script> ? Hg0:call <SID>Backward()<CR>?
161endif
162
163fun! s:Forward()
164  " Searching forward
165  noremap <script> n H$nzt<SID>L
166  if &wrap
167    noremap <script> N H0Nzt<SID>L
168  else
169    noremap <script> N Hg0Nzt<SID>L
170  endif
171  cnoremap <silent> <script> <CR> <CR>:cunmap <lt>CR><CR>zt<SID>L
172endfun
173
174fun! s:Backward()
175  " Searching backward
176  if &wrap
177    noremap <script> n H0nzt<SID>L
178  else
179    noremap <script> n Hg0nzt<SID>L
180  endif
181  noremap <script> N H$Nzt<SID>L
182  cnoremap <silent> <script> <CR> <CR>:cunmap <lt>CR><CR>zt<SID>L
183endfun
184
185call s:Forward()
186
187" Quitting
188noremap q :q<CR>
189
190" Switch to editing (switch off less mode)
191map v :silent call <SID>End()<CR>
192fun! s:End()
193  set ma
194  if exists('s:lz')
195    let &lz = s:lz
196  endif
197  unmap h
198  unmap H
199  unmap <Space>
200  unmap <C-V>
201  unmap f
202  unmap <C-F>
203  unmap z
204  unmap <Esc><Space>
205  unmap F
206  unmap d
207  unmap <C-D>
208  unmap <CR>
209  unmap <C-N>
210  unmap e
211  unmap <C-E>
212  unmap j
213  unmap <C-J>
214  unmap b
215  unmap <C-B>
216  unmap w
217  unmap <Esc>v
218  unmap u
219  unmap <C-U>
220  unmap k
221  unmap y
222  unmap <C-Y>
223  unmap <C-P>
224  unmap <C-K>
225  unmap r
226  unmap <C-R>
227  unmap R
228  unmap g
229  unmap <
230  unmap <Esc><
231  unmap G
232  unmap >
233  unmap <Esc>>
234  unmap %
235  unmap p
236  unmap n
237  unmap N
238  unmap q
239  unmap v
240  unmap /
241  unmap ?
242endfun
243
244" vim: sw=2
245