AddParam Question

Post reply

❤Follow Topic(3)

0 favourites

6 posts

Noncentz705
- Joined 28 Apr, 2013
- 15 topics • 201 posts
1

2 Nov, 2014
Quote

So let's say I've defined an expression with two string parameters

AddStringParam("Opt1","Option1","");
AddStringParam("Opt2","Option2","");
AddExpression(5, ef_return_string, "myFunc, "My Plugin", "myFunc", "My Function");
[/code:fsil8fsp]

and then in a later version of the plugins life, I'd like to add another optional parameter to the expression.

[code:fsil8fsp]
AddStringParam("Opt1","Option1","");
AddStringParam("Opt2","Option2","");
AddStringParam("Opt3","Option3","");
AddExpression(5, ef_return_string, "myFunc, "My Plugin", "myFunc", "My Function");
[/code:fsil8fsp]

How would I add the parameter without breaking previous projects?
I get errors (...expects 2 parameters not 3). 

Could the editor just read the default value and slip it in if it's missing, 
or is there a optionalstringparam or something similar so my expressions can still take 2 params but could take 3 as well?
I don't think AddVariadicParams is what I'm looking for.

- Ashley Construct Team Founder
- Moderator
- - Joined 21 May, 2007
  - 667 topics • 30,052 posts
- 1
- 3 Nov, 2014
- Quote
The easiest thing to do is deprecate the expression (add the ef_deprecated flag) and add a new expression with a different name with the new parameter. This preserves backwards compatibility but forces new projects to use the new expression.

New parameters are automatically filled with a default for conditions and actions, but it's a lot harder to do for expressions since they are parsed from text when loading the project.
- Noncentz705
- - Joined 28 Apr, 2013
  - 15 topics • 201 posts
- 1
- 5 Nov, 2014
- Quote
Thanks at Ash , sorry for the late reply. It seems adding new parameters to actions and conditions causes errors as well? I've deprecated the old aces as a work around.
Try Construct 3

Develop games in your browser. Powerful, performant & highly capable.
Try Now Construct 3 users don't see these ads
- Ashley Construct Team Founder
- Moderator
- - Joined 21 May, 2007
  - 667 topics • 30,052 posts
- 1
- 5 Nov, 2014
- Quote
It shouldn't do, I've done it with official features in the past. You should provide more information otherwise I can only guess at what could possibly have gone wrong.
- rexrainbow
- - Joined 4 Apr, 2011
  - 222 topics • 4,532 posts
- 1
- 6 Nov, 2014
- Quote
In expression, add "ef_variadic_parameters", see official array plugin -

AddNumberParam("X", "The X index (0-based) of the array value to get.", "0");

AddExpression(0, ef_return_any | ef_variadic_parameters, "Get value at", "Array", "At", "Get value from the array. Add second or third parameters to specify Y and Z indices.");

In action or condition, if the type of parameter added on the last is not a "object type", it could not be filled automatically. i.e, editor could not find a default "object type" in this case.

Noncentz705
- Joined 28 Apr, 2013
- 15 topics • 201 posts
1

10 Nov, 2014
Quote

Ash

---------------------------
Construct 2 Check failure
---------------------------
Check failure!  This is probably a bug:

Calling IsActive() on empty Expression class

Condition: parsed
File: projects\Expression.cpp
Line: 189
Function: bool __thiscall Expression::IsActive(void) const
Build: release 187 (32-bit) checked
Component: Construct 2 IDE
(Last Win32 error: 0)
[/code:3l57d569]

Condition 1, and 2 had to be deprecated because of this issue,
Action 0, 2 , 5, 9 I'd like to add the commented string param
Expression 4 and 5 had to be deprecated because of this issue

[url=https://dl.dropboxusercontent.com/u/139218609/examples/Plugins/jszip_beta.zip]Test[/url]

You could open one of the test capx's in the project folder after attempting to add a parameter.

Post reply

❤Follow Topic(3)