Method IsFunctionDefinition

source/script.cpp:1613–1649

bool Script::IsFunctionDefinition(LPTSTR aBuf, LPTSTR aNextBuf)
// Helper function for LoadIncludedFile().
// Caller passes in an aBuf containing a candidate line such as "function(x, y)"
// Caller has ensured that aBuf is rtrim'd.
// Caller should pass NULL for aPendingFunctionHasBrace to indicate that function definitions (open-brace
// on same line as function) are not allowed.  When non-NULL *and* aBuf is a function call/def,
// *aPendingFunctionHasBrace is set to true if a brace is present at the end, or false otherwise.
// In addition, any open-brace is removed from aBuf in this mode.
{
	LPTSTR action_end = find_identifier_end(aBuf);
	// Can't be a function definition or call without an open-parenthesis as first char found by the above.
	// action_end points at the first character which is not usable in an identifier, such as a space, tab
	// colon or other operator symbol.  As a result, it can't be:
	// 1) a hotstring, since they always start with at least one colon that would be caught immediately as 
	//    first-expr-char-is-not-open-parenthesis by the above.
	// 2) Any kind of math or assignment, such as var:=(x+y) or var+=(x+y).
	// The only things it could be other than a function call or function definition are:
	// Normal label that ends in single colon but contains an open-parenthesis prior to the colon, e.g. Label(x):
	// Single-line hotkey such as KeyName::MsgBox.  But (:: is the only valid hotkey where *action_end == '(',
	// and that's handled by excluding action_end == aBuf.
	if (*action_end != '(' || action_end == aBuf)
		return false;
	// Is it a control flow statement, such as "if(condition)"?
	*action_end = '\0';
	bool is_control_flow = ConvertActionType(aBuf);
	*action_end = '(';
	if (is_control_flow)
		return false;
	// It's not control flow.
	LPTSTR param_end = action_end + FindExprDelim(action_end, ')', 1);
	if (*param_end != ')')
		return false;
	LPTSTR next_token = omit_leading_whitespace(param_end + 1);
	return *next_token == 0 && *aNextBuf == '{' // Brace on next line.
		|| *next_token == '{' && next_token[1] == 0 // Brace on same line.
		|| *next_token == '=' && next_token[1] == '>'; // Fn() => expr
}