Small improvementsHEADmaster

5 files changed, 25 insertions, 11 deletions

diff --git a/lpeg.html b/lpeg.html
index b31d575..bd54294 100644
--- a/lpeg.html
+++ b/lpeg.html
@@ -53,19 +53,22 @@
 <h2><a name="intro">Introduction</a></h2>
 
 <p>
-<em>LPeg</em> is a new pattern-matching library for Lua,
+<em>LPeg</em> is a pattern-matching library for Lua,
 based on
 <a href="//bford.info/packrat/">
 Parsing Expression Grammars</a> (PEGs).
 This text is a reference manual for the library.
+For those starting with LPeg,
+<a href="https://www.inf.puc-rio.br/~roberto/docs/lpeg-primer.pdf">
+Mastering LPeg</a> presents a good tutorial.
 For a more formal treatment of LPeg,
 as well as some discussion about its implementation,
 see
 <a href="//www.inf.puc-rio.br/~roberto/docs/peg.pdf">
 A Text Pattern-Matching Tool based on Parsing Expression Grammars</a>.
-(You may also be interested in my
+You may also be interested in my
 <a href="//vimeo.com/1485123">talk about LPeg</a>
-given at the III Lua Workshop.)
+given at the III Lua Workshop.
 </p>
 
 <p>
@@ -664,13 +667,22 @@ produces values for each match.
 
 <p>
 Usually,
-LPeg does not specify when (and if) it evaluates its captures.
-(As an example,
-consider the pattern <code>lpeg.P"a" / func / 0</code>.
-Because the "division" by 0 instructs LPeg to throw away the
-results from the pattern,
-it is not specified whether LPeg will call <code>func</code>.)
+LPeg does not specify when, if, or how many times it evaluates its captures.
 Therefore, captures should avoid side effects.
+As an example,
+LPeg may or may not call <code>func</code> in the pattern
+<code>lpeg.P"a" / func / 0</code>,
+given that the <a href="#cap-num">"division" by 0</a>
+instructs LPeg to throw away the
+results from the pattern.
+Similarly, a capture nested inside a <a href="#cap-g">named group</a>
+may be evaluated only when that group is referred in a
+<a href="#cap-b">back capture</a>;
+if there are multiple back captures,
+the group may be evaluated multiple times.
+</p>
+
+<p>
 Moreover,
 captures cannot affect the way a pattern matches a subject.
 The only exception to this rule is the
diff --git a/lptree.c b/lptree.c
index 475b0c3..a176ad9 100644
--- a/lptree.c
+++ b/lptree.c
@@ -1123,7 +1123,7 @@ static int verifyrule (lua_State *L, TTree *tree, unsigned short *passed,
         return verifyerror(L, passed, npassed);  /* error */
       else {
         passed[npassed++] = tree->key;  /* add rule to path */
-        /* return verifyrule(L, sib1(tree), passed, npassed); */
+        /* return verifyrule(L, sib1(tree), passed, npassed, nb); */
         tree = sib1(tree); goto tailcall;
       }
     case TGrammar:
diff --git a/lptypes.h b/lptypes.h
index 3f860b9..b5cea44 100644
--- a/lptypes.h
+++ b/lptypes.h
@@ -34,6 +34,7 @@
 
 #define lua_rawlen              lua_objlen
 
+#undef luaL_newlib
 #define luaL_setfuncs(L,f,n)    luaL_register(L,NULL,f)
 #define luaL_newlib(L,f)        luaL_register(L,"lpeg",f)
 
diff --git a/makefile b/makefile
index 41a2928..82a95bb 100644
--- a/makefile
+++ b/makefile
@@ -1,5 +1,6 @@
 LIBNAME = lpeg
 LUADIR = ./lua/
+#LUADIR = /home/roberto/prj/lua/
 
 COPT = -O2 -DNDEBUG
 # COPT = -O0 -DLPEG_DEBUG -g
diff --git a/test.lua b/test.lua
index d0b82da..3241408 100755
--- a/test.lua
+++ b/test.lua
@@ -47,7 +47,7 @@ end
 print"General tests for LPeg library"
 
 assert(type(m.version) == "string")
-print(m.version)
+print(m.version, _VERSION)
 assert(m.type("alo") ~= "pattern")
 assert(m.type(io.input) ~= "pattern")
 assert(m.type(m.P"alo") == "pattern")