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Parse lists and {a,b,c} syntax (What is this even called?)

--- a/example.pl

+++ b/example.pl

@@ -11,4 +11,9 @@

 could_be_friends(Person1, Person2) :-

 	likes(Person1, Thing1),

 	likes(Person2, Thing2),

-	Thing1 = Thing2.

\ No newline at end of file

+	Thing1 = Thing2.

+

+list1(A) :- A = [1,2,3,4].

+list2(A) :- A = [a,b|c].

+

+curly(A) :- A = {one,two,three}.

\ No newline at end of file

--- a/parser.c

+++ b/parser.c

@@ -59,7 +59,8 @@

 	CurlyBracketLeftTok	= 1<<10, /* 1024 */

 	CurlyBracketRightTok	= 1<<11, /* 2048 */

 	CommaTok		= 1<<12, /* 4096 */

-	EofTok			= 1<<13, /* 8192 */

+	PipeTok			= 1<<13, /* 8192 */

+	EofTok			= 1<<14, /* 16384 */

 };

 static Biobuf *parsein;

@@ -72,6 +73,8 @@

 void nexttoken(void);

 Term *fullterm(int, Rune *, Term *);

 Term *term(void);

+Term *listterm(int);

+Term *curlybracketterm(void);

 Term *compound(void);

 Term *parseoperators(Term *);

 void match(int);

@@ -162,6 +165,12 @@

 		result = mkatom(L",");

 		match(CommaTok);

 		break;

+	case SquareBracketLeftTok:

+		result = listterm(1);

+		break;

+	case CurlyBracketLeftTok:

+		result = curlybracketterm();

+		break;

 	default:

 		print("Cant parse term of token type %d\n", lookahead.tag);

 		syntaxerror("term");

@@ -172,6 +181,38 @@

 }

 Term *

+listterm(int start)

+{

+	if(start)

+		match(SquareBracketLeftTok);

+

+	if(lookahead.tag == SquareBracketRightTok){

+		match(SquareBracketRightTok);

+		return mkatom(L"[]");

+	}else if(lookahead.tag == PipeTok){

+		match(PipeTok);

+		Term *t = fullterm(SquareBracketRightTok, nil, nil);

+		match(SquareBracketRightTok);

+		return t;

+	}else{

+		Term *t = fullterm(CommaTok|PipeTok|SquareBracketRightTok, nil, nil);

+		if(lookahead.tag == CommaTok)

+			match(CommaTok);

+		t->next = listterm(0);

+		return mkcompound(L".", 2, t);

+	}

+}

+

+Term *

+curlybracketterm(void)

+{

+	match(CurlyBracketLeftTok);

+	Term *result = fullterm(CurlyBracketRightTok, nil, nil);

+	match(CurlyBracketRightTok);

+	return mkcompound(L"{}", 1, result);

+}

+

+Term *

 compound(void)

 {

 	Rune *name = lookahead.text;

@@ -368,6 +409,7 @@

 	if(peek == L'%'){

 		while(peek != L'\n')

 			peek = Bgetrune(parsein);

+		Bgetrune(parsein);

 		peek = Bgetrune(parsein);

 	}

@@ -520,7 +562,7 @@

 	}

 	/* Other */

-	if(runestrchr(L",.()]}", peek)){

+	if(runestrchr(L",.()]}|", peek)){

 		switch(peek){

 		case L',': lookahead.tag = CommaTok; break;

 		case L'(': lookahead.tag = ParenLeftTok; break;

@@ -527,6 +569,7 @@

 		case L')': lookahead.tag = ParenRightTok; break;

 		case L']': lookahead.tag = SquareBracketRightTok; break;

 		case L'}': lookahead.tag = CurlyBracketRightTok; break;

+		case L'|': lookahead.tag = PipeTok; break;

 		}

 		return;

 	}