local utf = unicode.utf8
-if not buffers then buffers = { } end
-if not buffers.visualizers then buffers.visualizers = { } end
-if not buffers.visualizers.lam then buffers.visualizers.lam = { } end
+vis = buffers.newvisualizer("lam")
-buffers.visualizers.lam.colors = {
+local colors = {
"prettytwo",
"prettyone",
"prettythree",
"prettyfour"
}
-buffers.visualizers.lam.symbols = {
+-- Symbols that should have a different representation
+local symbols = {
[' '] = {repr = '\\obs '},
['_'] = {repr = '\\_'},
['->'] = {repr = '\\rightarrow'},
-- The default * sits very high above the baseline, \ast (u+2217) looks
-- better.
['*'] = {repr = '\\ast'},
+ ['~'] = {repr = '\\sim'},
}
-buffers.visualizers.lam.keywords = {
+
+-- Keywords that should be bold
+local keywords = {
['case'] = {},
['of'] = {},
['let'] = {},
['in'] = {},
}
-
-function buffers.visualizers.lam.take_symbol(str)
- -- See if str starts with a symbol, and return the remaining
- -- string and that symbol. If no symbol from the table is matched,
- -- just returns the first character.
- -- We can do a lookup directly, since symbols can be different in
- -- length, so we just loop over all symbols, trying them in turn.
- for symbol,props in pairs(buffers.visualizers.lam.symbols) do
+-- See if str starts with a symbol, and return the remaining string and that
+-- symbol. If no symbol from the table is matched, just returns the first
+-- character. We can do a lookup directly, since symbols can be different in
+-- length, so we just loop over all symbols, trying them in turn.
+local function take_symbol(str)
+ for symbol,props in pairs(symbols) do
-- Try to remove symbol from the start of str
symbol, newstr = utf.match(str, "^(" .. symbol .. ")(.*)")
if symbol then
-- Take a single word from str, if posible. Returns the rest of the string and
-- the word taken.
-function buffers.visualizers.lam.take_word(str)
- res, newstr = utf.match(str, "^(%a[%a%d_]+)(.*)")
+local function take_word(str)
+ -- A word must always start with a-z (in particular, λ is not a valid
+ -- start of a word).
+ res, newstr = utf.match(str, "^([a-zA-Z][%a%d_]+)(.*)")
return res, newstr or str
end
-- Tries to match each of the patterns and returns the captures of the first
-- matching pattern (up to 5 captures are supported). Returns nil when nothing
-- matches.
-function buffers.visualizers.lam.match_mul(str, patterns)
+local function match_mul(str, patterns)
for i, pat in ipairs(patterns) do
a, b, c, d, e = utf.match(str, pat)
if a then
return nil
end
-function buffers.visualizers.lam.begin_of_buffer()
- -- Initially allow subscripts using _ or just appending a number (later,
- -- we will add extra patterns here.
- submatches = {"^(.*)_([%a%d,]+)$", "^(.*[^%d])(%d+)$"}
- -- This stores all the bases we've encountered so far (to prevent
- -- duplicates). For each of them there will be a pattern in submatches
- -- above.
- bases = {}
-end
-
-function buffers.visualizers.lam.end_of_buffer()
- -- Reset submatches and bases, since flush_line can be called without
- -- begin / end_of_buffer for \type.
- buffers.visualizers.lam.begin_of_buffer()
- bases = nil
-end
-
-function buffers.visualizers.lam.do_subscripts(word)
- local match_mul = buffers.visualizers.lam.match_mul
+-- Find any subscripts in the given word and typeset them
+local function do_subscripts(word)
base, sub = match_mul(res, submatches)
if sub then
word = base .. "\\low{" .. sub .. "}"
-- After a word has been used as a base, allow subscripts
-- without _, even for non-numbers.
- if bases and not bases[base] then
+ if not bases[base] then
-- Register that we've added this base
bases[base] = true
-- Add a pattern for this base
return word
end
-function buffers.visualizers.lam.flush_line(str,nested)
+function vis.begin_of_display()
+ -- Initially allow subscripts using _ or just appending a number (later,
+ -- we will add extra patterns here.
+ submatches = {"^(.*)_([%a%d,]+)$", "^(.*[^%d])(%d+)$"}
+ -- This stores all the bases we've encountered so far (to prevent
+ -- duplicates). For each of them there will be a pattern in submatches
+ -- above.
+ bases = {}
+end
+
+-- Make things work for inline typeing (e.g., \type{}) as well.
+vis.begin_of_inline = vis.begin_of_display
+vis.end_of_inline = vis.end_of_display
+
+function vis.flush_line(str,nested)
local result, state = { }, 0
local finish, change = buffers.finish_state, buffers.change_state
- local take_symbol = buffers.visualizers.lam.take_symbol
- local take_word = buffers.visualizers.lam.take_word
- local do_subscripts = buffers.visualizers.lam.do_subscripts
-- Set the colorscheme, which is used by finish_state and change_state
- buffers.currentcolors = buffers.visualizers.lam.colors
+ buffers.currentcolors = colors
while str ~= "" do
local found = false
local word, symbol
-- See if the next token is a word
word, str = take_word(str)
if word then
- if buffers.visualizers.lam.keywords[res] then
+ if keywords[res] then
-- Make all keywords bold
word = "{\\bold " .. word .. "}"
else
buffers.flush_result(result,nested)
end
--- Call end_of_buffer once to set up submatches (since \type doesn't call
--- begin_of_buffer / end_of_buffer).
-buffers.visualizers.lam.end_of_buffer()
-
-- vim: set sw=4 sts=4 expandtab ai:
projects / matthijs / master-project / report.git / blobdiff