Implement continuation for #if* #endif.

lib/MetaProcessor/InputValidator.cpp

@@ -22,10 +22,28 @@ namespace cling {
       MetaLexer::LexPunctuatorAndAdvance(curPos, Tok);
       int kind = (int)Tok.getKind();
 
-      // If there is " or ' we don't need to look for balancing until we
-      // enounter matching " or '
+      if (kind == tok::hash) {
+        // Handle #ifdef ...
+        //          ...
+        //        #endif
+        MetaLexer Lexer(curPos);
+        Lexer.Lex(Tok);
+        if (Tok.getKind() == tok::ident) {
+          if (Tok.getIdent().startswith("if")) {
+            Res = kIncomplete;
+            m_ParenStack.push(kind);
+          }
+          else if (Tok.getIdent().startswith("end")) {
+            assert(m_ParenStack.top() == kind && "No coresponding # to pop?");
+            m_ParenStack.pop();
+          }
+          break;
+        }
+      }
+
       if (kind >= (int)tok::quote && kind <= (int)tok::apostrophe) {
-        MetaLexer::LexQuotedStringAndAdvance(curPos, Tok);
+        // If there is " or ' we don't need to look for balancing until we
+        // enounter matching " or '
         if (kind != (int)Tok.getKind()) {
            Res = kIncomplete;
            m_ParenStack.push(kind);

lib/MetaProcessor/MetaLexer.cpp

@@ -46,7 +46,7 @@ namespace cling {
     switch (C) {
     case '[': case ']': case '(': case ')': case '{': case '}': case '"':
     case '\'': case '\\': case ',': case '.': case '!': case '?': case '>':
-    case '&': case '@':
+    case '&': case '#': case '@':
       // INTENTIONAL FALL THROUGHs
       return LexPunctuator(C, Tok);
 
@@ -115,6 +115,7 @@ namespace cling {
     case '>'  : Tok.setKind(tok::greater); break;
     case '@' : Tok.setKind(tok::at); break;
     case '&'  : Tok.setKind(tok::ampersand); break;
+    case '#'  : Tok.setKind(tok::hash); break;
     case '\0' : Tok.setKind(tok::eof); Tok.setLength(0); break;// if static call
     default: Tok.setLength(0); break;
     }

lib/MetaProcessor/MetaLexer.h

@@ -34,6 +34,7 @@ namespace cling {
       backslash,  // "\"
       greater,    // ">"
       ampersand,  // "&"
+      hash,       // "#"
       ident,      // (a-zA-Z)[(0-9a-zA-Z)*]
       raw_ident,  // .*^(' '|'\t')
       comment,    // //

test/Interfaces/evaluate.C

@@ -11,6 +11,11 @@
 #include "cling/Interpreter/Interpreter.h"
 #include "cling/Interpreter/Value.h"
 
+.rawInput 1
+#ifdef MACOS
+#endif // MACOS
+.rawInput 0
+
 cling::Value V;
 V // CHECK: (cling::Value &) <<<invalid>>> @0x{{.*}}