public Class ASTExpr

For now, we can only add two objects as strings; convert objects to Strings then cat.

For treat the names, phones as lists to be walked in lock step as n=names[i], p=phones[i].

Do a standard conversion of array attributes to a List. Wrap the array instead of copying like old version. Make an ArrayWrappedInList that knows to create an ArrayIterator.

A expr is normally just a string literal, but is still an AST that we must evaluate. The expr can be any expression such as a template include or string cat expression etc... Evaluate with its own writer so that we can convert to string and then reuse, don't want to compute all the time; must precompute w/o writing to output buffer.

Return the first attribute if multiple valued or the attribute itself if single-valued. Used in

Return the tree interpreted when this template is written out.

Return o.getPropertyName() given o and propertyName. If o is a stringtemplate then access it's attributes looking for propertyName instead (don't check any of the enclosing scopes; look directly into that object). Also try isXXX() for booleans. Allow Map as special case (grab value for key). Cache repeated requests for obj.prop within same group.

Call a string template with args and return result. Do not convert to a string yet. It may need attributes that will be available after this is inserted into another template.

Return the last attribute if multiple valued or the attribute itself if single-valued. Used in . This is pretty slow as it iterates until the last element. Ultimately, I could make a special case for a List or Vector.

Return the length of a multiple valued attribute or 1 if it is a single attribute. If attribute is null return 0. Special case several common collections and primitive arrays for speed. This method by Kay Roepke.

Return the everything but the first attribute if multiple valued or null if single-valued. Used in .

Return a new list w/o null values.

Normally StringTemplate tests presence or absence of attributes for adherence to my principles of separation, but some people disagree and want to change. For 2.0, if the object is a boolean, do something special. $if(boolean)$ will actually test the value. Now, this breaks my rules of entanglement listed in my paper, but it truly surprises programmers to have booleans always true. Further, the key to isolating logic in the model is avoiding operators (for which you need attribute values). But, no operator is needed to use boolean values. Well, actually I guess "!" (not) is an operator. Regardless, for practical reasons, I'm going to technically violate my rules as I currently have them defined. Perhaps for a future version of the paper I will refine the rules. Post 2.1, I added a check for non-null Iterators, Collections, ... with size==0 to return false. TJP 5/1/2005

Overrides java.lang.Object.toString.

Doc from java.lang.Object.toString.

Returns a string representation of the object.

Returns:String

a string representation of the object.

Return all but the last element. trunc(x)=null if x is single-valued.

Implements abstract org.antlr.stringtemplate.language.Expr.write.

To write out the value of an ASTExpr, invoke the evaluator in eval.g to walk the tree writing out the values. For efficiency, don't compute a bunch of strings and then pack them together. Write out directly. Compute separator and wrap expressions, save as strings so we don't recompute for each value in a multi-valued attribute or expression. If they set anchor option, then inform the writer to push current char position.

How to spit out an object. If it's not a StringTemplate nor a List, just do o.toString(). If it's a StringTemplate, do o.write(out). If it's a Vector, do a write(out, o.elementAt(i)) for all elements. Note that if you do something weird like set the values of a multivalued tag to be vectors, it will effectively flatten it. If self is an embedded template, you might have specified a separator arg; used when is a vector.