fix '?' token ambiguity, add STRUCT to identifier rule

antlr · Jan 31, 2025 · aca468c · aca468c
1 parent 464f891
commit aca468c
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Showing 4 changed files with 20 additions and 1 deletion.
diff --git a/swift/swift5/Cpp/SwiftSupport.cpp b/swift/swift5/Cpp/SwiftSupport.cpp
@@ -248,6 +248,10 @@ bool SwiftSupport::isBinaryOp(antlr4::TokenStream* tokens) {
     bool nextIsWS = isRightOperatorWS(nextToken);
     //String text = tokens.getText(Interval.of(start, stop));
     //System.out.println("isBinaryOp: '"+prevToken+"','"+text+"','"+nextToken+"' is "+result);
+    // accept only '??'' as binary operator
+    if (currentToken->getType() == Swift5Lexer::QUESTION && start == stop) {
+        return false;
+    }
     if (prevIsWS) {
         return nextIsWS;
     } else {

diff --git a/swift/swift5/Java/SwiftSupport.java b/swift/swift5/Java/SwiftSupport.java
@@ -252,6 +252,10 @@ public static boolean isBinaryOp(TokenStream tokens) {
         boolean nextIsWS = isRightOperatorWS(nextToken);
         //String text = tokens.getText(Interval.of(start, stop));
         //System.out.println("isBinaryOp: '"+prevToken+"','"+text+"','"+nextToken+"' is "+result);
+        // accept only '??'' as binary operator
+        if (currentToken.getType() == Swift5Lexer.QUESTION && start == stop) {
+            return false;
+        }
         if (prevIsWS) {
             return nextIsWS;
         } else {

diff --git a/swift/swift5/Swift5Parser.g4 b/swift/swift5/Swift5Parser.g4
@@ -1326,7 +1326,7 @@ forced_value_suffix
     ;
 
 optional_chaining_suffix
-    : {!this.isBinaryOp(_input)}? QUESTION
+    : {!this.isBinaryOp(_input) && _input.get(_input.index()-1).getType()!=WS}? QUESTION
     ;
 
 // Function Call Expression
@@ -1565,6 +1565,7 @@ identifier
         | SELF_BIG
         | SET
         | CLASS
+        | STRUCT
         | GETTER
         | SETTER
         | OPERATOR

diff --git a/swift/swift5/examples/Functions and Closures/Contents.swift b/swift/swift5/examples/Functions and Closures/Contents.swift
@@ -108,7 +108,17 @@ printTwoStrings { (_ x: String, _ y: String) in
     print(x, y)
 }
 
+// : Accepts 'struct' as external parameter name
+public func create<T>(struct s: T) {
+    print(s)
+}
+
+create(struct: 1)
 
+// : Return expression with two QUESTION tokens
+public func GetString<T>(_ s: T, _ val: Int) -> String? {
+    return val == 0 ? s as? String : nil
+}
 
 
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