justify.vim (9159B)
1 " Function to left and right align text. 2 " 3 " Written by: Preben "Peppe" Guldberg <c928400@student.dtu.dk> 4 " Created: 980806 14:13 (or around that time anyway) 5 " Revised: 001103 00:36 (See "Revisions" below) 6 7 8 " function Justify( [ textwidth [, maxspaces [, indent] ] ] ) 9 " 10 " Justify() will left and right align a line by filling in an 11 " appropriate amount of spaces. Extra spaces are added to existing 12 " spaces starting from the right side of the line. As an example, the 13 " following documentation has been justified. 14 " 15 " The function takes the following arguments: 16 17 " textwidth argument 18 " ------------------ 19 " If not specified, the value of the 'textwidth' option is used. If 20 " 'textwidth' is zero a value of 80 is used. 21 " 22 " Additionally the arguments 'tw' and '' are accepted. The value of 23 " 'textwidth' will be used. These are handy, if you just want to specify 24 " the maxspaces argument. 25 26 " maxspaces argument 27 " ------------------ 28 " If specified, alignment will only be done, if the longest space run 29 " after alignment is no longer than maxspaces. 30 " 31 " An argument of '' is accepted, should the user like to specify all 32 " arguments. 33 " 34 " To aid user defined commands, negative values are accepted aswell. 35 " Using a negative value specifies the default behaviour: any length of 36 " space runs will be used to justify the text. 37 38 " indent argument 39 " --------------- 40 " This argument specifies how a line should be indented. The default is 41 " to keep the current indentation. 42 " 43 " Negative values: Keep current amount of leading whitespace. 44 " Positive values: Indent all lines with leading whitespace using this 45 " amount of whitespace. 46 " 47 " Note that the value 0, needs to be quoted as a string. This value 48 " leads to a left flushed text. 49 " 50 " Additionally units of 'shiftwidth'/'sw' and 'tabstop'/'ts' may be 51 " added. In this case, if the value of indent is positive, the amount of 52 " whitespace to be added will be multiplied by the value of the 53 " 'shiftwidth' and 'tabstop' settings. If these units are used, the 54 " argument must be given as a string, eg. Justify('','','2sw'). 55 " 56 " If the values of 'sw' or 'tw' are negative, they are treated as if 57 " they were 0, which means that the text is flushed left. There is no 58 " check if a negative number prefix is used to change the sign of a 59 " negative 'sw' or 'ts' value. 60 " 61 " As with the other arguments, '' may be used to get the default 62 " behaviour. 63 64 65 " Notes: 66 " 67 " If the line, adjusted for space runs and leading/trailing whitespace, 68 " is wider than the used textwidth, the line will be left untouched (no 69 " whitespace removed). This should be equivalent to the behaviour of 70 " :left, :right and :center. 71 " 72 " If the resulting line is shorter than the used textwidth it is left 73 " untouched. 74 " 75 " All space runs in the line are truncated before the alignment is 76 " carried out. 77 " 78 " If you have set 'noexpandtab', :retab! is used to replace space runs 79 " with whitespace using the value of 'tabstop'. This should be 80 " conformant with :left, :right and :center. 81 " 82 " If joinspaces is set, an extra space is added after '.', '?' and '!'. 83 " If 'cpoptions' include 'j', extra space is only added after '.'. 84 " (This may on occasion conflict with maxspaces.) 85 86 87 " Related mappings: 88 " 89 " Mappings that will align text using the current text width, using at 90 " most four spaces in a space run and keeping current indentation. 91 nmap _j :%call Justify('tw',4)<CR> 92 vmap _j :call Justify('tw',4)<CR> 93 " 94 " Mappings that will remove space runs and format lines (might be useful 95 " prior to aligning the text). 96 nmap ,gq :%s/\s\+/ /g<CR>gq1G 97 vmap ,gq :s/\s\+/ /g<CR>gvgq 98 99 100 " User defined command: 101 " 102 " The following is an ex command that works as a shortcut to the Justify 103 " function. Arguments to Justify() can be added after the command. 104 com! -range -nargs=* Justify <line1>,<line2>call Justify(<f-args>) 105 " 106 " The following commands are all equivalent: 107 " 108 " 1. Simplest use of Justify(): 109 " :call Justify() 110 " :Justify 111 " 112 " 2. The _j mapping above via the ex command: 113 " :%Justify tw 4 114 " 115 " 3. Justify visualised text at 72nd column while indenting all 116 " previously indented text two shiftwidths 117 " :'<,'>call Justify(72,'','2sw') 118 " :'<,'>Justify 72 -1 2sw 119 " 120 " This documentation has been justified using the following command: 121 ":se et|kz|1;/^" function Justify(/+,'z-g/^" /s/^" //|call Justify(70,3)|s/^/" / 122 123 " Revisions: 124 " 001103: If 'joinspaces' was set, calculations could be wrong. 125 " Tabs at start of line could also lead to errors. 126 " Use setline() instead of "exec 's/foo/bar/' - safer. 127 " Cleaned up the code a bit. 128 " 129 " Todo: Convert maps to the new script specific form 130 131 " Error function 132 function! Justify_error(message) 133 echohl Error 134 echo "Justify([tw, [maxspaces [, indent]]]): " . a:message 135 echohl None 136 endfunction 137 138 139 " Now for the real thing 140 function! Justify(...) range 141 142 if a:0 > 3 143 call Justify_error("Too many arguments (max 3)") 144 return 1 145 endif 146 147 " Set textwidth (accept 'tw' and '' as arguments) 148 if a:0 >= 1 149 if a:1 =~ '^\(tw\)\=$' 150 let tw = &tw 151 elseif a:1 =~ '^\d\+$' 152 let tw = a:1 153 else 154 call Justify_error("tw must be a number (>0), '' or 'tw'") 155 return 2 156 endif 157 else 158 let tw = &tw 159 endif 160 if tw == 0 161 let tw = 80 162 endif 163 164 " Set maximum number of spaces between WORDs 165 if a:0 >= 2 166 if a:2 == '' 167 let maxspaces = tw 168 elseif a:2 =~ '^-\d\+$' 169 let maxspaces = tw 170 elseif a:2 =~ '^\d\+$' 171 let maxspaces = a:2 172 else 173 call Justify_error("maxspaces must be a number or ''") 174 return 3 175 endif 176 else 177 let maxspaces = tw 178 endif 179 if maxspaces <= 1 180 call Justify_error("maxspaces should be larger than 1") 181 return 4 182 endif 183 184 " Set the indentation style (accept sw and ts units) 185 let indent_fix = '' 186 if a:0 >= 3 187 if (a:3 == '') || a:3 =~ '^-[1-9]\d*\(shiftwidth\|sw\|tabstop\|ts\)\=$' 188 let indent = -1 189 elseif a:3 =~ '^-\=0\(shiftwidth\|sw\|tabstop\|ts\)\=$' 190 let indent = 0 191 elseif a:3 =~ '^\d\+\(shiftwidth\|sw\|tabstop\|ts\)\=$' 192 let indent = substitute(a:3, '\D', '', 'g') 193 elseif a:3 =~ '^\(shiftwidth\|sw\|tabstop\|ts\)$' 194 let indent = 1 195 else 196 call Justify_error("indent: a number with 'sw'/'ts' unit") 197 return 5 198 endif 199 if indent >= 0 200 while indent > 0 201 let indent_fix = indent_fix . ' ' 202 let indent = indent - 1 203 endwhile 204 let indent_sw = 0 205 if a:3 =~ '\(shiftwidth\|sw\)' 206 let indent_sw = &sw 207 elseif a:3 =~ '\(tabstop\|ts\)' 208 let indent_sw = &ts 209 endif 210 let indent_fix2 = '' 211 while indent_sw > 0 212 let indent_fix2 = indent_fix2 . indent_fix 213 let indent_sw = indent_sw - 1 214 endwhile 215 let indent_fix = indent_fix2 216 endif 217 else 218 let indent = -1 219 endif 220 221 " Avoid substitution reports 222 let save_report = &report 223 set report=1000000 224 225 " Check 'joinspaces' and 'cpo' 226 if &js == 1 227 if &cpo =~ 'j' 228 let join_str = '\(\. \)' 229 else 230 let join_str = '\([.!?!] \)' 231 endif 232 endif 233 234 let cur = a:firstline 235 while cur <= a:lastline 236 237 let str_orig = getline(cur) 238 let save_et = &et 239 set et 240 exec cur . "retab" 241 let &et = save_et 242 let str = getline(cur) 243 244 let indent_str = indent_fix 245 let indent_n = strlen(indent_str) 246 " Shall we remember the current indentation 247 if indent < 0 248 let indent_orig = matchstr(str_orig, '^\s*') 249 if strlen(indent_orig) > 0 250 let indent_str = indent_orig 251 let indent_n = strlen(matchstr(str, '^\s*')) 252 endif 253 endif 254 255 " Trim trailing, leading and running whitespace 256 let str = substitute(str, '\s\+$', '', '') 257 let str = substitute(str, '^\s\+', '', '') 258 let str = substitute(str, '\s\+', ' ', 'g') 259 let str_n = strdisplaywidth(str) 260 261 " Possible addition of space after punctuation 262 if exists("join_str") 263 let str = substitute(str, join_str, '\1 ', 'g') 264 endif 265 let join_n = strdisplaywidth(str) - str_n 266 267 " Can extraspaces be added? 268 " Note that str_n may be less than strlen(str) [joinspaces above] 269 if strdisplaywidth(str) <= tw - indent_n && str_n > 0 270 " How many spaces should be added 271 let s_add = tw - str_n - indent_n - join_n 272 let s_nr = strlen(substitute(str, '\S', '', 'g') ) - join_n 273 let s_dup = s_add / s_nr 274 let s_mod = s_add % s_nr 275 276 " Test if the changed line fits with tw 277 if 0 <= (str_n + (maxspaces - 1)*s_nr + indent_n) - tw 278 279 " Duplicate spaces 280 while s_dup > 0 281 let str = substitute(str, '\( \+\)', ' \1', 'g') 282 let s_dup = s_dup - 1 283 endwhile 284 285 " Add extra spaces from the end 286 while s_mod > 0 287 let str = substitute(str, '\(\(\s\+\S\+\)\{' . s_mod . '}\)$', ' \1', '') 288 let s_mod = s_mod - 1 289 endwhile 290 291 " Indent the line 292 if indent_n > 0 293 let str = substitute(str, '^', indent_str, '' ) 294 endif 295 296 " Replace the line 297 call setline(cur, str) 298 299 " Convert to whitespace 300 if &et == 0 301 exec cur . 'retab!' 302 endif 303 304 endif " Change of line 305 endif " Possible change 306 307 let cur = cur + 1 308 endwhile 309 310 norm ^ 311 312 let &report = save_report 313 314 endfunction 315 316 " EOF vim: tw=78 ts=8 sw=4 sts=4 noet ai