X-Git-Url: https://git.stderr.nl/gitweb?p=matthijs%2Fmaster-project%2Freport.git;a=blobdiff_plain;f=pret-lam.lua;h=f14b962ba2cd162a8f9743e73aeef8e30b695776;hp=1011b19e1672e24fb3cb572eaff45e4a4ffa17d5;hb=1108517b5c84c5fc7c8aa21ac60cd33e28487519;hpb=9fb83d4c3f0511c8e6e0b584d18370eba508a29b

diff --git a/pret-lam.lua b/pret-lam.lua
index 1011b19..f14b962 100644
--- a/pret-lam.lua
+++ b/pret-lam.lua
@@ -17,6 +17,7 @@ buffers.visualizers.lam.colors = {
     "prettyfour"
 }
 
+-- Symbols that should have a different representation
 buffers.visualizers.lam.symbols = {
     [' '] = {repr = '\\obs '},
     ['_'] = {repr = '\\_'},
@@ -24,8 +25,11 @@ buffers.visualizers.lam.symbols = {
     -- The default * sits very high above the baseline, \ast (u+2217) looks
     -- better.
     ['*'] = {repr = '\\ast'},
+    ['~'] = {repr = '\\sim'},
 }
 
+
+-- Keywords that should be bold
 buffers.visualizers.lam.keywords = {
     ['case'] = {},
     ['of'] = {},
@@ -33,13 +37,11 @@ buffers.visualizers.lam.keywords = {
     ['in'] = {},
 }
 
-
+-- 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.
 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
         -- Try to remove symbol from the start of str 
         symbol, newstr = utf.match(str, "^(" .. symbol .. ")(.*)")
@@ -61,7 +63,9 @@ end
 -- 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_]+)(.*)")
+        -- 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
 
@@ -78,23 +82,7 @@ function buffers.visualizers.lam.match_mul(str, patterns)
     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
-
+-- Find any subscripts in the given word and typeset them
 function buffers.visualizers.lam.do_subscripts(word)
     local match_mul = buffers.visualizers.lam.match_mul
     base, sub = match_mul(res, submatches)
@@ -102,7 +90,7 @@ function buffers.visualizers.lam.do_subscripts(word)
         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
@@ -112,6 +100,16 @@ function buffers.visualizers.lam.do_subscripts(word)
     return word
 end
 
+function buffers.visualizers.lam.begin_of_buffer(type, name)
+    -- 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.flush_line(str,nested)
     local result, state = { }, 0
     local finish, change = buffers.finish_state, buffers.change_state
@@ -146,8 +144,4 @@ function buffers.visualizers.lam.flush_line(str,nested)
     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: