13.6 Expressions

An expression is a formula that defines a computation or retrieval of a value. In a project file the value of an expression is either a string or a list of strings. A string value in an expression is either a literal, the current value of a variable, an external value, an attribute reference, or a concatenation operation.

Syntax:

     expression ::=
       term {& term}
     
     term ::=
       string_literal |
       string_list |
       <variable_>name |
       external_value |
       attribute_reference
     
     string_literal ::=
       (same as Ada)
     
     string_list ::=
       ( <string_>expression { , <string_>expression } )

13.6.1 Concatenation

The following concatenation functions are defined:

       function "&" (X : String;      Y : String)      return String;
       function "&" (X : String_List; Y : String)      return String_List;
       function "&" (X : String_List; Y : String_List) return String_List;