– This file has code for converting errors to user-friendly format, with colors, – line numbers, code excerpts, and so on. require “containers” Text = require ‘text’ C = require ‘colors’

box = (text)-> maxline = 0 for line in text\gmatch(“[^\n]+”) maxline = math.max(maxline, #(line\gsub(“\027%[[0-9;]m”,””))) ret = (“\n”..text)\gsub “\n([^\n])”, (line)-> linelen = #(line\gsub(“\027%[[0-9;]*m”,””)) return “\n#{line}#{(“ “)\rep(maxline-linelen)} “..C(‘reset’) return ret\sub(2,-1), max_line

formaterror = (err)-> context = err.context or 2 errline, errlinenum, errlinepos = err.source\lineinfoat(err.start) – TODO: better handle multi-line errors errsize = math.min((err.stop - err.start), (#errline-errlinepos) + 1) nlindicator = (errlinepos > #errline) and “ “ or ““ fmtstr = “ %#{#tostring(errlinenum+context)}d|"

pointer = (" ")\rep(err_linepos+#fmt_str\format(0)-1)..("^")\rep(err_size)
--pointer = if err_size >= 2
--    (" ")\rep(err_linepos+#fmt_str\format(0)-1).."╚#{("═")\rep(err_size-2)}╝"
--else
--    (" ")\rep(err_linepos+#fmt_str\format(0)-1).."⬆"

err_msg = C('bold red', err.title or "Error")..C('red', " at #{err.filename or '???'}:#{err_linenum},#{err_linepos}")
err_msg ..= "\n" unless COLOR_ENABLED
lines = err.source\lines!
for i=err_linenum-context,err_linenum-1
    if line = lines[i]
        err_msg ..= "\n"..C('dim', fmt_str\format(i))..line
if err_line
    before = err_line\sub(1, err_linepos-1)
    during = err_line\sub(err_linepos,err_linepos+err_size-1)
    after = err_line\sub(err_linepos+err_size, -1)
    err_line = before..C('black on red', during..nl_indicator)..after
    err_msg ..= "\n"..C('dim', fmt_str\format(err_linenum))..err_line
_, err_linenum_end, err_linepos_end = err.source\line_info_at(err.stop)
err_linenum_end or= err_linenum
if err_linenum_end == err_linenum
    err_msg ..= "\n#{pointer}"
else
    for i=err_linenum+1,err_linenum_end
        if line = lines[i]
            if i == err_linenum_end
                during, after = line\sub(1,err_linepos_end-1), line\sub(err_linepos_end,-1)
                err_msg ..= "\n"..C('dim', fmt_str\format(i))..C('black on red', during)..after
            else
                err_msg ..= "\n"..C('dim', fmt_str\format(i))..C('black on red', line)
        if i > err_linenum+1 + 5
            err_msg ..= "\n       ...\n"
            break

box_width = 70
err_text = C('black on white', " "..err.error\wrapped_to(box_width, 16)\gsub("\n", "\n"..C('black on white').." "))
if err.hint
    err_text ..= "\n"..C('italic black on white', (" Suggestion: #{err.hint}")\wrapped_to(box_width, 16)\gsub("\n", "\n"..C('italic black on white').." "))
err_msg ..= "\n "..box(err_text)\gsub("\n", "\n ")
err_msg ..= "\n" unless COLOR_ENABLED

for i=err_linenum_end+1,err_linenum_end+context
    if line = lines[i]
        err_msg ..= "\n"..C('dim', fmt_str\format(i))..line
err_msg ..= "\n" unless COLOR_ENABLED
return err_msg

return format_error