More notes about Lua quirks.

1 files changed, 15 insertions, 0 deletions

diff --git a/LuaSL/src/LuaSL_compile.c b/LuaSL/src/LuaSL_compile.c
index b9d6d48..1007c89 100644
--- a/LuaSL/src/LuaSL_compile.c
+++ b/LuaSL/src/LuaSL_compile.c
@@ -30,6 +30,9 @@ LSL_Token LSL_Tokens[] =
 // QUIRK - Seems to be some disagreement about BOOL_AND/BOOL_OR precedence.  Either they are equal, or OR is higher.
 // QUIRK - No boolean short circuiting.
 // QUIRK - Booleans and conditionals are executed right to left.  Or maybe not, depending on who you believe.
+// LUA   - Short circiuts boolean operations, and goes left to right.
+// LUA   - "and" returns its first argument if it is false, otherwise, it returns its second argument. "or" returns its first argument if it is not false, otherwise it returns its second argument.
+//           Note that the above means that "and/or" can return any type.
     {LSL_BOOL_OR,               ST_BOOLEAN,             "||",   LSL_RIGHT2LEFT,                         NULL, evaluateOperationToken},
     {LSL_BIT_OR,                ST_BITWISE,             "|",    LSL_LEFT2RIGHT,                         NULL, evaluateOperationToken},
     {LSL_BIT_XOR,               ST_BITWISE,             "^",    LSL_LEFT2RIGHT,                         NULL, evaluateOperationToken},
@@ -41,6 +44,7 @@ LSL_Token LSL_Tokens[] =
     {LSL_LESS_EQUAL,            ST_COMPARISON,          "<=",   LSL_RIGHT2LEFT,                         NULL, evaluateOperationToken},
     {LSL_GREATER_THAN,          ST_COMPARISON,          ">",    LSL_RIGHT2LEFT,                         NULL, evaluateOperationToken},
     {LSL_LESS_THAN,             ST_COMPARISON,          "<",    LSL_RIGHT2LEFT,                         NULL, evaluateOperationToken},
+// LUA   - comparisons are always false if they are different types.  Tables, userdata, and functions are compared by reference.  Strings campare in alphabetical order, depending on current locale.
     {LSL_RIGHT_SHIFT,           ST_BITWISE,             ">>",   LSL_LEFT2RIGHT,                         NULL, evaluateOperationToken},
     {LSL_LEFT_SHIFT,            ST_BITWISE,             "<<",   LSL_LEFT2RIGHT,                         NULL, evaluateOperationToken},
     {LSL_CONCATENATE,           ST_ADD,                 "+",    LSL_LEFT2RIGHT,                         NULL, evaluateOperationToken},
@@ -54,6 +58,17 @@ LSL_Token LSL_Tokens[] =
     {LSL_NEGATION,              ST_NEGATE,              "-",    LSL_RIGHT2LEFT | LSL_UNARY,             NULL, evaluateOperationToken},
     {LSL_BOOL_NOT,              ST_BOOL_NOT,            "!",    LSL_RIGHT2LEFT | LSL_UNARY,             NULL, evaluateOperationToken},
     {LSL_BIT_NOT,               ST_BIT_NOT,             "~",    LSL_RIGHT2LEFT | LSL_UNARY,             NULL, evaluateOperationToken},
+
+// LUA precedence - (it has no bit operators, at least not until 5.2, but LuaJIT has them.)
+// or
+// and
+// < > <= >= ~= ==
+// ..
+// + -
+// * /
+// not negate
+// exponentiation (^)
+
     {LSL_TYPECAST_CLOSE,        ST_NONE,                ")",    LSL_RIGHT2LEFT | LSL_UNARY,             NULL, evaluateNoToken},
     {LSL_TYPECAST_OPEN,         ST_NONE,                "(",    LSL_RIGHT2LEFT | LSL_UNARY,             NULL, evaluateOperationToken},
     {LSL_ANGLE_CLOSE,           ST_NONE,                ">",    LSL_LEFT2RIGHT | LSL_CREATION,          NULL, evaluateNoToken},