Merge pull request #203 from tiffany1618/add-default-cpp-params

Add default C++ function parameters
nasa · Jan 6, 2023 · 9976f75 · 9976f75
2 parents a6172a4 + dd67c66
commit 9976f75
Show file tree

Hide file tree

Showing 3 changed files with 20 additions and 9 deletions.
diff --git a/compiler/lib/src/main/scala/codegen/CppWriter/CppDoc.scala b/compiler/lib/src/main/scala/codegen/CppWriter/CppDoc.scala
@@ -84,7 +84,8 @@ object CppDoc {
     case class Param(
       t: Type,
       name: String,
-      comment: Option[String] = None
+      comment: Option[String] = None,
+      default: Option[String] = None
     )
     sealed trait SVQualifier
     case object NonSV extends SVQualifier

diff --git a/compiler/lib/src/main/scala/codegen/CppWriter/CppDocHppWriter.scala b/compiler/lib/src/main/scala/codegen/CppWriter/CppDocHppWriter.scala
@@ -10,6 +10,11 @@ object CppDocHppWriter extends CppDocWriter {
     case None => s
   }
 
+  def addParamDefault(s: String, defaultOpt: Option[String]): String = defaultOpt match {
+    case Some(default) => s"$s = $default"
+    case None => s
+  }
+
   def closeIncludeGuard: List[Line] = lines(
     """|
        |#endif"""
@@ -25,14 +30,17 @@ object CppDocHppWriter extends CppDocWriter {
 
   def paramString(p: CppDoc.Function.Param): String = {
     val s1 = CppDocCppWriter.paramString(p)
-    val s2 = addParamComment(s1, p.comment)
-    s2
+    val s2 = addParamDefault(s1, p.default)
+    val s3 = addParamComment(s2, p.comment)
+    s3
   }
 
   def paramStringComma(p: CppDoc.Function.Param): String = {
-    val s1 = CppDocCppWriter.paramStringComma(p)
-    val s2 = addParamComment(s1, p.comment)
-    s2
+    val s1 = CppDocCppWriter.paramString(p)
+    val s2 = addParamDefault(s1, p.default)
+    val s3 = s"$s2,"
+    val s4 = addParamComment(s3, p.comment)
+    s4
   }
 
   def writeAccessTag(tag: String): List[Line] = List(
@@ -43,7 +51,7 @@ object CppDocHppWriter extends CppDocWriter {
   def writeParams(prefix: String, params: List[CppDoc.Function.Param]): List[Line] = {
     if (params.length == 0) lines(s"$prefix()")
     else if (params.length == 1 && params.head.comment.isEmpty)
-      lines(s"$prefix(" ++ CppDocCppWriter.paramString(params.head) ++ ")")
+      lines(s"$prefix(" ++ paramString(params.head) ++ ")")
     else {
       val head :: tail = params.reverse
       val paramLines = (writeParam(head) :: tail.map(writeParamComma(_))).reverse

diff --git a/compiler/lib/test/codegen/CppWriter/Main.scala b/compiler/lib/test/codegen/CppWriter/Main.scala
@@ -136,12 +136,14 @@ object Program extends LineUtils {
                         Function.Param(
                           Type("const double", None),
                           "x",
-                          Some("This is parameter x")
+                          Some("This is parameter x"),
+                          Some("0.0")
                         ),
                         Function.Param(
                           Type("const int", None),
                           "y",
-                          Some("This is parameter y")
+                          Some("This is parameter y"),
+                          Some("0")
                         )
                       ),
                       retType = Type("void", None),