/**
Because callbacks are handled in Lua, they still have to look like a Lua
callback. The Script wrapper class can't "rename" them.
**/
int
TestScript::Script_PrintNumber (lua_State* state)
{
// But we can enable Script support using a special constructor.
Script script(state);
// Retrieve the number passed on the stack.
Script::Object numberObj = script.GetObject(1);
// Verify it is a number and print it.
if (numberObj.IsNumber())
printf("%f\n", numberObj.GetNumber());
// No return values.
return 0;
}
/**
Demonstrates walking an array table.
**/
void
TestScript::DoScriptArrayTest()
{
Script script;
script.DoFile("ScriptArrayTest.scr");
Script::Object testTableObj = script.GetGlobals().GetByName("TestArray");
// or script.GetGlobal("TestArray");
for (int i = 1; ; ++i)
{
Script::AutoBlock block(script); // Automatic stack fixups.
Script::Object entryObj = testTableObj.GetByIndex(i);
if (entryObj.IsNil())
break;
if (entryObj.IsNumber()) // IsNumber() must ALWAYS come first.
printf("%f\n", entryObj.GetNumber());
else if (entryObj.IsString()) // IsString() returns true for a number or string.
printf("%s\n", entryObj.GetString());
}
}
/**
Writes a Lua object to a text file.
**/
static void
WriteObject(Script& script, FILE* file, const char* name,
Script::Object value, unsigned int indentLevel)
{
// If there is nothing in the variable, then don't write it.
if (value.IsNil())
return;
// If the variable is user data or a function, then don't write it.
if (value.IsUserData() || value.IsFunction())
{
return;
}
// Indent the line the number of spaces for the current indentation level.
const unsigned int INDENT_SIZE = 4;
const unsigned int indentSpaces = indentLevel * INDENT_SIZE;
IndentFile(file, indentSpaces);
// If the object has a name, write it out.
if (name)
fprintf(file, "%s = ", name);
// If the object's value is a number, write it as a number.
if (value.IsNumber())
fprintf(file, "%.16g", value.GetNumber());
// Or if the object's value is a string, write it as a quoted string.
else if (value.IsString())
fprintf(file, "\"%s\"", value.GetString());
// Otherwise, see if the object's value is a table.
else if (value.IsTable())
{
// Write the table header.
fputs("\n", file);
IndentFile(file, indentSpaces);
fputs("{\n", file);
// Rename, just for ease of reading.
Script::Object table = value;
// upperIndex is the upper index value of a sequential numerical array
// items.
int upperIndex = 1;
bool wroteSemi = false;
bool hasSequential = false;
// Block to search for array items.
{
// Pop the stack state when done.
Script::AutoBlock block (script);
// Grab index 1 and index 2 of the table.
Script::Object value1 = table.GetByIndex(1);
Script::Object value2 = table.GetByIndex(2);
// If they both exist, then there is a sequential list.
if (!value1.IsNil() && !value2.IsNil())
{
// Cycle through the list.
bool firstSequential = true;
for (; ; ++upperIndex)
{
// Restore the stack state each iteration.
Script::AutoBlock block_ (script);
// Try retrieving the table entry at upperIndex.
Script::Object value = table.GetByIndex(upperIndex);
// If it doesn't exist, then exit the loop.
if (value.IsNil())
break;
// Only add the comma and return if not on the first item.
if (!firstSequential)
fputs(",\n", file);
// Write the object as an unnamed entry.
WriteObject(script, file, NULL, value, indentLevel + 1);
// We've definitely passed the first item now.
firstSequential = false;
}
}
}
// Did we find any sequential table values?
if (upperIndex > 1)
{
hasSequential = true;
}
// Cycle through the table.
int i;
script.PushNil();
while ((i = script.Next(table.GetStackIndex())) != 0)
{
char keyName[255];
// Retrieve the table entry's key and value.
Script::Object key = script.GetObject(script.GetTop() - 1);
Script::Object value = script.GetObject(script.GetTop());
// Is the key a number?
if (key.IsNumber())
{
// Yes, were there sequential array items in this table?
if (hasSequential)
{
// Is the array item's key an integer?
float realNum = key.GetNumber();
int intNum = (int)realNum;
if (realNum == (float)intNum)
{
// Yes. Is it between 1 and upperIndex?
if (intNum >= 1 && intNum < upperIndex)
{
// We already wrote it as part of the sequential
// list.
script.Pop();
continue;
}
}
}
// Build the table entry name for the number.
sprintf(keyName, "[%.16g]", key.GetNumber());
}
else
{
// Build the table entry name for the string key name.
strcpy(keyName, key.GetString());
}
// If we wrote a sequential list, the value we're about to write
// is not nil, and we haven't written the semicolon to separate
// the sequential table entries from the keyed table entries...
if (hasSequential && !value.IsNil() && !wroteSemi)
{
// Then add a comma (for good measure) and the semicolon.
fputs(", ;\n", file);
wroteSemi = true;
}
// Write the table entry.
WriteObject(script, file, keyName, value, indentLevel + 1);
// Add a comma after the table entry.
fputs(",\n", file);
// Go to the next item.
script.Pop();
}
// If we wrote a sequential list and haven't written a semicolon, then
// there were no keyed table entries. Just write the final comma.
if (hasSequential && !wroteSemi)
{
fputs(",\n", file);
}
// Indent, with the intent of closing up the table.
IndentFile(file, indentSpaces);
// If the indentation level is 0, then we're at the root position.
if (indentLevel == 0)
{
// Add a couple extra returns for readability's sake.
fputs("}\n\n", file);
}
else
{
// Close the table. The comma is written when WriteObject()
// returns from the recursive call.
fputs("}", file);
}
}
// If the indentation level is at the root, then add a return to separate
// the lines.
if (indentLevel == 0)
{
fputs("\n", file);
}
}