diff options
Diffstat (limited to 'doc/language')
| -rw-r--r-- | doc/language/keyword/cpsc-keyword-class.7.md | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/doc/language/keyword/cpsc-keyword-class.7.md b/doc/language/keyword/cpsc-keyword-class.7.md index bcb299b..ebeb98e 100644 --- a/doc/language/keyword/cpsc-keyword-class.7.md +++ b/doc/language/keyword/cpsc-keyword-class.7.md @@ -38,7 +38,7 @@ Classes retain record value semantics: zero initialization, whole-value copying, A constructor is a PROCEDURE named NEW, following guide section 10.2. It may be PUBLIC or PRIVATE; FUNCTION NEW and global PROCEDURE NEW are errors. Member names are case insensitive, so New and new also name the constructor. Multiple NEW procedures are allowed when every definition specifies OVERLOAD and their parameter signatures differ. Explicit `Object.NEW(arguments)`, `CALL Object.NEW(arguments)` and `this.NEW(arguments)` behave like ordinary member calls and may be repeated; they do not zero the object or reconstruct its fields. -`DECLARE Object : ClassName`, `DECLARE Object : ClassName()` and `DECLARE Object : ClassName(arguments)` zero the object's storage, construct its fields recursively in declaration order, then call its NEW procedure. These automatic DECLARE, field and array calls are compiler extensions. Array elements and class-valued fields in records or classes use parameterless construction, before the enclosing constructor runs. A required constructor argument cannot be omitted; supplying arguments to a class without NEW is an error. Empty parentheses are allowed for a class without NEW. Constructor arguments after ARRAY OF are unsupported. A declaration executed again, such as inside a loop, first destroys its previous live incarnation, then zeroes and constructs its original storage again. +`DECLARE Object : ClassName` zeroes the object's storage and constructs its fields recursively in declaration order; it then calls NEW only when the class has a parameterless NEW. Otherwise the object stays unconstructed until `Object <- NEW ClassName(arguments)` binds it, as in guide section 10.2. `DECLARE Object : ClassName(arguments)` always calls the matching NEW, so `ClassName()` is an error for a class whose NEW requires arguments, and supplying arguments to a class without NEW is an error. These automatic DECLARE, field and array calls are compiler extensions. Array elements and class-valued fields in records or classes follow the plain DECLARE rule, before the enclosing constructor runs. Constructor arguments after ARRAY OF are unsupported. A declaration executed again, such as inside a loop, first destroys its previous live incarnation, then zeroes and constructs its original storage again. An `OVERLOAD PROCEDURE NEW(BYREF Other : ClassName)` defines a copy constructor. BYVAL class lvalue arguments and RETURN of class lvalues invoke it; a same-class BYVAL constructor is rejected. Classes without one retain bitwise copying for fields without STRING ownership. Records and BYVAL arrays recursively clone STRING-bearing fields or elements. Other owning class fields retain the existing shallow-copy limitations. Class results transfer ownership directly into BYVAL arguments, RETURN and ordinary assignment without an assignment overload. Discarded results and temporary receivers live until the statement ends, including exception exits. Ordinary user BYREF calls still require bare variables; constructor calls can bind temporaries. |