Missing pretty print for VariableDeclaration

Issue #130 resolved
Loïc Girault created an issue

VariableDeclaration has no prettyPrint method. Here is an implementation :

public void VariableDeclaration.prettyPrint(PrettyPrinter out) {
    out.print(" ");
    if (hasInit()) {
      out.print(" = ");

Comments (10)

  1. Loïc Girault reporter

    Also about VariableDeclaration, the following equation in LookupVariable.jrag seems to be missing :

    eq VariableDeclaration.variableDeclaration(String name) = declaresVariable(name) ? this : null ;

    I haven't looked into the parser, I suppose it generates a VarDeclStmt even when a VariableDeclaration would suffice. This could explain why the above equation is not needed. Since I'm doing refactoring in the AST I introduced directly a VariableDeclaration and had a bug because of this missing (?) equation.

  2. Jesper Öqvist

    Yes, the parser only builds VarDeclStmt nodes with VariableDecl children. VarDeclStmt has a non-terminal list child containing VariableDeclaration nodes (SingleDecl), and name lookup always points to the non-terminal VariableDeclaration nodes. I wish VariableDecl and VariableDeclaration had more distinct names, but it might not be worth it to rename them now. A better naming scheme might be to rename VariableDeclartion to VariableDeclNta.

    Edit: oops, the name lookup actually points to VariableDeclaration nodes.

  3. Loïc Girault reporter

    l don't get the following defintion in java.ast VarDeclStmt : Stmt ::= Modifiers TypeAccess:Access VariableDecl* /SingleDecl:VariableDeclaration*/; Is SingleDecl meant to be an alias for when the size of the VariableDecl list is one ?

  4. Jesper Öqvist

    /SingleDecl:VariableDeclaration*/ is a list of VariableDeclaration that is non-terminal, meaning that the nodes in the list are computed by an attribute. SingleDecl is the name of the list.

  5. Loïc Girault reporter

    Thank you for your answer. I understand the jastadd syntax, but I mean in this case, for which attribute does SingleDecl exist ? With a quick grep, it seems that everywhere SingleDecl is used, the VariableDecl list should have been used instead.

  6. Jesper Öqvist

    The SingleDecl list is used as a way of avoiding a JastAdd rewrite. VarDeclStmt used to be rewritten to a list of VariableDeclaration, but this type of list rewrite is unsafe to use so instead individual VariableDeclaration nodes are computed by the VarDeclStmt.getSingleDecl(int) attribute. This means that the VariableDecl children of VarDeclStmt do not need to be used at all, since they have less information (modifiers, type) than VariableDeclaration.

  7. Jesper Öqvist

    I feel stupid now. This discussion made me realise that a better solution for ExtendJ would be to completely remove VariableDeclaration from the abstract grammar, and instead add NTA type and modifier children to VariableDecl:

    VariableDecl ::= /Modifiers/ /TypeAccess:Access/ <ID:String> Dims* [Init:Expr];
  8. Loïc Girault reporter

    Well wasnt this caused because extendj is supposed to map the java specification ? and Modifiers and TypeAcccess shouldn't be optional rather than non terminal ? And making VariableDecl a Stmt wouldn't break anything elsewhere ?

    Anyway, I'm happy if my questions help you find some improvements for extendj

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