From 7c0e4fbb1d1f0d19d11c7417c55a305654ab1c83 Mon Sep 17 00:00:00 2001 From: Robin Haberkorn Date: Tue, 8 Apr 2025 23:26:38 +0300 Subject: tightened rules for specifying modifiers * Instead of separate stand-alone commands, they are now allowed only immediately in front of the commands that accept them. * The order is still insignificant if both `@` and `:` are accepted. * The number of colon modifiers is now also checked. We basically get this for free. * `@` has syntactic significance, so it could not be set conditionally anyway. Still, it was possible to provoke bugs were `@` was interpreted conditionally as in `@ 2`. * Even when not causing bugs, a mistyped `@` would often influence the __next__ command, causing unexpected behavior, for instance when typing `@(233C)W`. * While it was theoretically possible to set `:` conditionally, it could also be "passed through" accidentally to some command where it wasn't expected as in `:Ifoo$ C`. I do not know of any real useful application or idiom of a conditionally set `:`. If there would happen to be some kind of useful application, `:'` and `:|` could be re-allowed easily, though. * I was condidering introducing a common parser state for modified commands, but that would have been tricky and introduce a lot of redundant command lists. So instead, we now simply everywhere check for excess modifiers. To simplify this task, teco_machine_main_transition_t now contains flags signaling whether the transition is allowed with `@` or `:` modifiers set. It currently only has to be checked in the start state, after `E` and `F`. --- src/parser.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'src/parser.c') diff --git a/src/parser.c b/src/parser.c index f4f7595..044a741 100644 --- a/src/parser.c +++ b/src/parser.c @@ -355,6 +355,13 @@ teco_machine_main_transition_input(teco_machine_main_t *ctx, return NULL; } + if ((ctx->modifier_at && !transitions[chr].modifier_at) || + (ctx->mode == TECO_MODE_NORMAL && + ctx->modifier_colon > transitions[chr].modifier_colon)) { + teco_error_modifier_set(error, chr); + return NULL; + } + if (ctx->mode == TECO_MODE_NORMAL && transitions[chr].transition_cb) { /* * NOTE: We could also just let transition_cb return a boolean... -- cgit v1.2.3