" vim: set sw=3 sts=3: " Awk indent script. It can handle multi-line statements and expressions. " It works up to the point where the distinction between correct/incorrect " and personal taste gets fuzzy. Drop me an e-mail for bug reports and " reasonable style suggestions. " " Bugs: " ===== " - Some syntax errors may cause erratic indentation. " - Same for very unusual but syntacticly correct use of { } " - In some cases it's confused by the use of ( and { in strings constants " - This version likes the closing brace of a multiline pattern-action be on " character position 1 before the following pattern-action combination is " formatted " Author: " ======= " Erik Janssen, ejanssen@itmatters.nl " " History: " ======== " 26-04-2002 Got initial version working reasonably well " 29-04-2002 Fixed problems in function headers and max line width " Added support for two-line if's without curly braces " Fixed hang: 2011 Aug 31 " Only load this indent file when no other was loaded. if exists("b:did_indent") finish endif let b:did_indent = 1 setlocal indentexpr=GetAwkIndent() " Mmm, copied from the tcl indent program. Is this okay? setlocal indentkeys-=:,0# " Only define the function once. if exists("*GetAwkIndent") finish endif " This function contains a lot of exit points. It checks for simple cases " first to get out of the function as soon as possible, thereby reducing the " number of possibilities later on in the difficult parts function! GetAwkIndent() " Find previous line and get it's indentation let prev_lineno = s:Get_prev_line( v:lnum ) if prev_lineno == 0 return 0 endif let prev_data = getline( prev_lineno ) let ind = indent( prev_lineno ) " Increase indent if the previous line contains an opening brace. Search " for this brace the hard way to prevent errors if the previous line is a " 'pattern { action }' (simple check match on /{/ increases the indent then) if s:Get_brace_balance( prev_data, '{', '}' ) > 0 return ind + &sw endif let brace_balance = s:Get_brace_balance( prev_data, '(', ')' ) " If prev line has positive brace_balance and starts with a word (keyword " or function name), align the current line on the first '(' of the prev " line if brace_balance > 0 && s:Starts_with_word( prev_data ) return s:Safe_indent( ind, s:First_word_len(prev_data), getline(v:lnum)) endif " If this line starts with an open brace bail out now before the line " continuation checks. if getline( v:lnum ) =~ '^\s*{' return ind endif " If prev line seems to be part of multiline statement: " 1. Prev line is first line of a multiline statement " -> attempt to indent on first ' ' or '(' of prev line, just like we " indented the positive brace balance case above " 2. Prev line is not first line of a multiline statement " -> copy indent of prev line let continue_mode = s:Seems_continuing( prev_data ) if continue_mode > 0 if s:Seems_continuing( getline(s:Get_prev_line( prev_lineno )) ) " Case 2 return ind else " Case 1 if continue_mode == 1 " Need continuation due to comma, backslash, etc return s:Safe_indent( ind, s:First_word_len(prev_data), getline(v:lnum)) else " if/for/while without '{' return ind + &sw endif endif endif " If the previous line doesn't need continuation on the current line we are " on the start of a new statement. We have to make sure we align with the " previous statement instead of just the previous line. This is a bit " complicated because the previous statement might be multi-line. " " The start of a multiline statement can be found by: " " 1 If the previous line contains closing braces and has negative brace " balance, search backwards until cumulative brace balance becomes zero, " take indent of that line " 2 If the line before the previous needs continuation search backward " until that's not the case anymore. Take indent of one line down. " Case 1 if prev_data =~ ')' && brace_balance < 0 while brace_balance != 0 && prev_lineno > 0 let prev_lineno = s:Get_prev_line( prev_lineno ) let prev_data = getline( prev_lineno ) let brace_balance=brace_balance+s:Get_brace_balance(prev_data,'(',')' ) endwhile let ind = indent( prev_lineno ) else " Case 2 if s:Seems_continuing( getline( prev_lineno - 1 ) ) let prev_lineno = prev_lineno - 2 let prev_data = getline( prev_lineno ) while prev_lineno > 0 && (s:Seems_continuing( prev_data ) > 0) let prev_lineno = s:Get_prev_line( prev_lineno ) let prev_data = getline( prev_lineno ) endwhile let ind = indent( prev_lineno + 1 ) endif endif " Decrease indent if this line contains a '}'. if getline(v:lnum) =~ '^\s*}' let ind = ind - &sw endif return ind endfunction " Find the open and close braces in this line and return how many more open- " than close braces there are. It's also used to determine cumulative balance " across multiple lines. function! s:Get_brace_balance( line, b_open, b_close ) let line2 = substitute( a:line, a:b_open, "", "g" ) let openb = strlen( a:line ) - strlen( line2 ) let line3 = substitute( line2, a:b_close, "", "g" ) let closeb = strlen( line2 ) - strlen( line3 ) return openb - closeb endfunction " Find out whether the line starts with a word (i.e. keyword or function " call). Might need enhancements here. function! s:Starts_with_word( line ) if a:line =~ '^\s*[a-zA-Z_0-9]\+\s*(' return 1 endif return 0 endfunction " Find the length of the first word in a line. This is used to be able to " align a line relative to the 'print ' or 'if (' on the previous line in case " such a statement spans multiple lines. " Precondition: only to be used on lines where 'Starts_with_word' returns 1. function! s:First_word_len( line ) let white_end = matchend( a:line, '^\s*' ) if match( a:line, '^\s*func' ) != -1 let word_end = matchend( a:line, '[a-z]\+\s\+[a-zA-Z_0-9]\+[ (]*' ) else let word_end = matchend( a:line, '[a-zA-Z_0-9]\+[ (]*' ) endif return word_end - white_end endfunction " Determine if 'line' completes a statement or is continued on the next line. " This one is far from complete and accepts illegal code. Not important for " indenting, however. function! s:Seems_continuing( line ) " Unfinished lines if a:line =~ '\(--\|++\)\s*$' return 0 endif if a:line =~ '[\\,\|\&\+\-\*\%\^]\s*$' return 1 endif " if/for/while (cond) eol if a:line =~ '^\s*\(if\|while\|for\)\s*(.*)\s*$' || a:line =~ '^\s*else\s*' return 2 endif return 0 endfunction " Get previous relevant line. Search back until a line is that is no " comment or blank and return the line number function! s:Get_prev_line( lineno ) let lnum = a:lineno - 1 let data = getline( lnum ) while lnum > 0 && (data =~ '^\s*#' || data =~ '^\s*$') let lnum = lnum - 1 let data = getline( lnum ) endwhile return lnum endfunction " This function checks whether an indented line exceeds a maximum linewidth " (hardcoded 80). If so and it is possible to stay within 80 positions (or " limit num of characters beyond linewidth) by decreasing the indent (keeping " it > base_indent), do so. function! s:Safe_indent( base, wordlen, this_line ) let line_base = matchend( a:this_line, '^\s*' ) let line_len = strlen( a:this_line ) - line_base let indent = a:base if (indent + a:wordlen + line_len) > 80 " Simple implementation good enough for the time being let indent = indent + 3 endif return indent + a:wordlen endfunction