improve/fix pretty-printing of Boolean grammars

grammarware · Jan 14, 2013 · 8b822b7 · 8b822b7
1 parent 4d493d2
commit 8b822b7
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Showing 3 changed files with 43 additions and 20 deletions.
diff --git a/shared/rascal/src/export/BNF.rsc b/shared/rascal/src/export/BNF.rsc
@@ -4,20 +4,20 @@ module export::BNF
 import lib::Rascalware;
 import syntax::BGF;
 
-public str pp(BGFGrammar bgf)
-	= (isEmpty(bgf.roots) ? "" : "Roots: <bgf.roots>\n")
-	+ pp(bgf.prods);
+public str pp(grammar([],BGFProdList ps)) = pp(ps);
+public default str pp(BGFGrammar bgf) = "Roots: <bgf.roots>\n<pp(bgf.prods)>";
 
-public str pp(BGFProdList ps) = joinStrings([pp(p) | p <- ps], "\n");
-public str pp(set[BGFProduction] ps) = joinStrings([pp(p) | p <- ps], "\n");
+public str pp(BGFProdList ps) = mapjoin(pp,ps,"\n");
 
-public str pp(BGFProduction p)
-	= (p.label!="" ? "[<p.label>] " : "")
-	+ "<p.lhs> ::= <pp(p.rhs)> ;";
+public str pp(set[BGFProduction] ps) = mapjoin(pp,ps,"\n");
 
-public str pp(BGFExprList es) = joinStrings([pp(e) | e <- es], " ");
+public str pp(production("",str lhs, BGFExpression rhs)) = "<lhs> ::= <pptop(rhs)> ;";
+public default str pp(BGFProduction p) = "[<p.label>] <p.lhs> ::= <pptop(p.rhs)> ;";
 
-public str ppc(BGFExprList es) = joinStrings([pp(e) | e <- es], " | ");
+str pptop(sequence(BGFExprList es)) = pp(es);
+default str pptop(BGFExpression e) = pp(e);
+
+public str pp(BGFExprList es) = mapjoin(pp,es," ");
 
 public str pp(epsilon()) = "EPSILON";
 public str pp(empty()) = "EMPTY";
@@ -26,13 +26,26 @@ public str pp(val(integer())) = "INT";
 public str pp(anything()) = "ANYTHING";
 public str pp(terminal(str s)) = "\"<s>\"";
 public str pp(nonterminal(str s)) = "<s>";
-public str pp(selectable(s,e)) = "<s>::<pp(e)>";
+public str pp(selectable(s,e)) = "<s>::<ppost(e)>";
 public str pp(sequence(L)) = "(<pp(L)>)";
-public str pp(choice(L)) = "(<ppc(L)>)";
+public str pp(choice(L)) = "(<mapjoin(pp,es," | ")>)";
+public str pp(allof(L)) = "(<mapjoin(pp,es," & ")>)";
 public str pp(marked(e)) = "\<<pp(e)>\>";
-public str pp(optional(e)) = "<pp(e)>?";
-public str pp(plus(e)) = "<pp(e)>+";
-public str pp(star(e)) = "<pp(e)>*";
+public str pp(optional(e)) = "<pppre(e)>?";
+public str pp(not(e)) = "¬<ppost(e)>";
+public str pp(plus(e)) = "<pppre(e)>+";
+public str pp(star(e)) = "<pppre(e)>*";
 public str pp(seplistplus(e1,e2)) = "{<pp(e1)> <pp(e2)>}+";
 public str pp(sepliststar(e1,e2)) = "{<pp(e1)> <pp(e2)>}*";
 public default str pp(BGFExpression e) = "UNKNOWN";
+
+// pretty-print prefix metasymbols in parenthesis, others as usual
+str pppre(BGFExpression e:not(e1)) = "(<pp(e)>)";
+str pppre(BGFExpression e:selectable(s,e)) = "(<pp(e)>)";
+default str pppre(BGFExpression e) = pp(e);
+
+// pretty-print postfix metasymbols in parenthesis, others as usual
+str ppost(BGFExpression e:optional(e1)) = "(<pp(e)>)";
+str ppost(BGFExpression e:plus(e1)) = "(<pp(e)>)";
+str ppost(BGFExpression e:star(e1)) = "(<pp(e)>)";
+default str ppost(BGFExpression e) = pp(e);
diff --git a/shared/rascal/src/lib/Rascalware.rsc b/shared/rascal/src/lib/Rascalware.rsc
@@ -34,6 +34,9 @@ public void println(str s) = IO::println(s);
 public str joinStrings([], _) = "";
 public str joinStrings(list[str] ss, str w) = (ss[0] | it + w + s | s <- tail(ss));
 
+public str mapjoin(&T1(&T2) f, list[&T2] xs, str sep) = joinStrings(mapper(xs,f),sep);
+public str mapjoin(&T1(&T2) f, set[&T2] xs, str sep) = joinStrings(toList(mapper(xs,f)),sep);
+
 //public bool multiseteq(list[&T] xs, list[&T] ys) = sort(xs) == sort(ys);
 public bool multiseteq(list[&T] xs, list[&T] ys) = sort(xs) == sort(ys);
 

diff --git a/shared/xsl/bgf2bnf.xslt b/shared/xsl/bgf2bnf.xslt
@@ -82,15 +82,24 @@
   </xsl:template>
 
   <xsl:template match="optional">
-    <xsl:apply-templates select="./*"/>
+    <xsl:choose>
+      <xsl:when test="bgf:expression/not or bgf:expression/selectable">
+        <xsl:text>(</xsl:text>
+        <xsl:apply-templates select="./*"/>
+        <xsl:text>)</xsl:text>
+      </xsl:when>
+      <xsl:otherwise>
+        <xsl:apply-templates select="./*"/>
+      </xsl:otherwise>
+    </xsl:choose>
     <xsl:text>?</xsl:text>
   </xsl:template>
 
   <!-- Boolean grammars support -->
   <xsl:template match="not">
     <xsl:text>!</xsl:text>
     <xsl:choose>
-      <xsl:when test="bgf:expression/optional or bgf:expression/not">
+      <xsl:when test="bgf:expression/optional or bgf:expression/plus or bgf:expression/star">
         <xsl:text>(</xsl:text>
         <xsl:apply-templates select="./*"/>
         <xsl:text>)</xsl:text>
@@ -138,9 +147,7 @@
     <xsl:value-of select="selector"/>
     <xsl:text>::</xsl:text>
     <xsl:choose>
-      <xsl:when test="local-name(bgf:expression/*) = 'star'
-                   or local-name(bgf:expression/*) = 'optional'
-                   or local-name(bgf:expression/*) = 'plus'">
+      <xsl:when test="bgf:expression/star or bgf:expression/optional or bgf:expression/plus">
         <xsl:text>(</xsl:text>
         <xsl:apply-templates select="bgf:expression"/>
         <xsl:text>)</xsl:text>