getMissingUserDefinedArguments work wrong in the latest version

[ninh-mech]

Issue title:

• getMissingUserDefinedArguments work wrong in the latest version

Issue content:

After I update to the latest version of mXparser, I got problem when use getMissingUserDefinedArguments fucntion.
Example: my expression in string: "300+Caster_Attack*3"

var expression = new Expression("300+Caster_Attack*3"); 
expression.getMissingUserDefinedArguments();

At v4.4.2 : that function will be return a string array [0] : "Caster_Attack"
At v.5.0.6 : that function will be return a string array [0]: "ast" [1]: "r_Attack"

If bug/question:

• MathParser.org-mXparser verssion: v.5.0.6
• Framework: .net

[mariuszgromada]

Hi,
Thank you for reporting. This is an "interesting" bug in the implementation of the implied multiplication. Please take a look at the following

Expression e = new Expression("300+Caster_Attack*3");
mXparser.consolePrintln(e.getCanonicalExpressionString());

The result
[mXparser-v.5.0.6] 300+C*ast*e*r_Attack*3

• "C" is a known keyword to the parser - the "C(n, k)" Binomial coefficient function. The error here is that the tokenizer should also look for the parentheses to be sure it can insert the multiplication sign.
• "e" is also a know keyword to the parser - the "e" Euler's number. Here everything is ok.

Options, as of now, that you have to fix this

• Use variable names that do not contain words known to the parser, see "e.getHelp()"
• Remove "C" and "e" built-in tokens

Expression e = new Expression("300+Caster_Attack*3");
mXparser.removeBuiltinTokens("C", "e");
mXparser.consolePrintln(e.getCanonicalExpressionString());

[mXparser-v.5.0.6] 300+Caster_Attack*3

• Turn off implied multiplication mode - locally

Expression e = new Expression("300+Caster_Attack*3");
e.disableImpliedMultiplicationMode();
mXparser.consolePrintln(e.getCanonicalExpressionString());

[mXparser-v.5.0.6] 300+Caster_Attack*3

• Turn off implied multiplication mode - globally

mXparser.disableImpliedMultiplicationMode();
Expression e = new Expression("300+Caster_Attack*3");
mXparser.consolePrintln(e.getCanonicalExpressionString());

[mXparser-v.5.0.6] 300+Caster_Attack*3

I hope this helps :-)

Best regards

[ninh-mech]

Thank for the quick response! Those information is so helpful. I knew the solution for this problem. Thanks

[mariuszgromada]

I think, I need to add the option in the implied multiplication allowing to select the variant

1. Implied Multiplication with parser builtin keywords
2. Implied Multiplication without parser builtin keywords

I will think more about it.

[mariuszgromada]

Fixed - Tokenization fix in case of Implied Multiplication and known keywords that are functions, but no parameters are provided

[mariuszgromada]

Dedicated Tutorial sections added

User defined arguments ->
Case 5: Possible conflict between Implied Multiplication and getting list of missing user defined arguments + recommended solutions
https://mathparser.org/mxparser-tutorial/user-defined-arguments/

User defined functions ->
Case 7: Possible conflict between Implied Multiplication and getting list of missing user defined functions + recommended solutions
https://mathparser.org/mxparser-tutorial/user-defined-functions/

Best regards