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--- rfc:ast_based_parsing_compilation_process [2012/09/04 19:49] – nikic
+++ rfc:ast_based_parsing_compilation_process [2012/09/07 12:54] – Add link regard functions parens nikic
@@ Line 24: / Line 24: @@
 ==== Elimination of various quirks ====
-Currently there is various quirks in the emitted opcodes which can be attributed to the use of a single-pass compiler. The simplest (and least important) example are the NOP opcodes that the compiler inserts at several places.
+Currently there is various quirks in the emitted opcodes which can be attributed to the use of a single-pass compiler. Some examples:
-A more interesting example is the fact that whenever you access a static member like ''Foo::$bar'' an unused compiled-variable for ''$bar'' is emitted. The compiler thinks that ''$bar'' is a normal variable and as such creates an
+  * The NOP opcodes that are inserted in several places. (Yes, this point isn't particularly important)
-unnecessary CV for it.
+  * Access of static variables using ''Foo::$bar'' creates an unused compiled variable for ''$bar'' (because the compiler thinks that it is a normal variable).
+  * ''$foo'' and ''($foo)'' behave differently in several places (the first can act as a reference, the second can not). For more info see http://stackoverflow.com/questions/6726589/parentheses-altering-semantics-of-function-call-result/6732876#6732876. (Some people claim that this is a feature, not a bug.)
-Other quirks (which actually influences the behavior) is caused by the separation of ''variable'' and ''expr_without_variable'' in the grammar. For example parentheses may cause subtle changes in behavior (''func($foo)''
-and ''%%func(($foo))%%'' have different behavior).
 All these can be eliminated when an AST is used.

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