Possible [for] bug, 1.13.8

[Samonella]

If I understand it right from the wiki, this should be perfectly valid code, iterating from 0 to 3:

Code: Select all

	[for]
		end=3
		[do]
			< stuff >
		[/do]
	[/for]

But it results in this error:

Code: Select all

error scripting/lua: lua/wml-flow.lua:149: attempt to perform arithmetic on a nil value (field 'step')
stack traceback:
	lua/wml-flow.lua:149: in local 'cmd'
	lua/wml-utils.lua:145: in field 'handle_event_commands'
	lua/wml-flow.lua:6: in function <lua/wml-flow.lua:5>
	[C]: in field 'fire_event'
	lua/wml-tags.lua:146: in local 'cmd'
	lua/wml-utils.lua:145: in field 'handle_event_commands'
	lua/wml-flow.lua:6: in function <lua/wml-flow.lua:5>

So I tried adding step=1 in the code, and then it worked fine. According to the wiki, 'step' should default to 1 (or -1, based on 'start' and 'end') so this is a bug?

[Tad_Carlucci]

Try this:

In wesnoth's data/lua/wml-flow.lua change line 102 from

Code: Select all

		if cfg.step then loop_lim.step = cfg_lit.step end

to

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		if cfg.step then loop_lim.step = cfg_lit.step else loop_lim.step = 1 end

and retest.

[Samonella]

That seems to have fixed it, at least for end>start. Thanks!

[Tad_Carlucci]

OK. If Celtic Minstrel doesn't beat me to it, I'll put together a PR with a more-complete solution.

[zookeeper]

5fdb73b9 was supposed to fix this exact issue, but I guess he didn't test it?

[Tad_Carlucci]

PR #1812 is the fix above. On reading the code, the case where 'end=-3' should do nothing with the wiki-specified default of 'step=1' so no additional checks seemed to be needed.

[WhiteWolf]

original post:

Sorry for the thread necromancy, but I'm getting a similar error message when using a for loop with 1.14.5:

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			    [if]
				[variable] # this is to make sure this variable is 13 or less
					name=previous_player.comp_score
					less_than=14
				[/variable] 
				... and some other conditions
				[then] 
					{VARIABLE can_say_true no}

					[for]
						start=$previous_player.comp_score    # if we're here, it's surely 13 or less
						step=1  # i tried actually specifying it due to the issues in this topic, didn't help
						end=14 
						[do]
							{CONVERT_DICE_SCORE iscore $i INVERT=yes} 
							{GET_SECOND_DIE isecond $iscore}

							[if]
								[variable]
									name=isecond
									equals=$current_player.second_die
								[/variable]
								[then]
									{VARIABLE can_say_true yes}
									[break]
									[/break]
								[/then]
							[/if]
						[/do]
					[/for]

Here's the error message it displays:

It seems to refer to this part in the for tag's definition:

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	while loop_condition() do
		for do_child in wml.child_range( cfg, "do" ) do
			local action = utils.handle_event_commands(do_child, "loop")
			if action == "break" then
				utils.set_exiting("none")
				goto exit
			elseif action == "continue" then
				utils.set_exiting("none")
				break
			elseif action ~= "none" then
				goto exit
			end
		end
---------->		wml.variables[i_var] = wml.variables[i_var] + loop_lim.step
	end
	::exit::
	utils.end_var_scope(i_var, save_i)
end

Is this a bug in the for tag, or am I doing something completely wrong and just don't see it?

EDIT: Sorry, it was my bad. One of the macros inside the [do] also used a variable named i and that caused the conflict.