Can you check for string parameters without a magic number?

Can you check for string parameters without a magic number? - Printable Version

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Can you check for string parameters without a magic number? - StephenG1CMZ - 11-15-2017 09:43 PM

You can check for floats, integers, lists etc. In PPL.

Can you detect a string too? Without using a magic number...

Code:

EXPORT STRINGMAGIC()

BEGIN

 PRINT(IFTE(TYPE(12.5)==DOM_FLOAT-1,STRING('DOM_FLOAT'),"NOT"));

 PRINT(IFTE(TYPE(#12)==DOM_INT-1,STRING('DOM_INT'),"NOT"));

 PRINT(IFTE(TYPE("ST")==DOM_STRING-1,STRING('DOM_STRING'),"OOPS"));

 PRINT(IFTE(TYPE("ST")==3-1,"It IS a THREE, NOT A STRING","OOPS"));

 PRINT(IFTE(TYPE({})==DOM_LIST-1,STRING('DOM_LIST'),"NOT"));

END;

yields:

DOM_FLOAT

DOM_INT

OOPS

It IS a THREE, NOT A STRING

DOM_LIST

Is there an alternative constant?

RE: Can you check for string parameters without a magic number? - Carlos295pz - 11-16-2017 12:20 AM

Exists:
type() → CAS
TYPE() → Home

RE: Can you check for string parameters without a magic number? - StephenG1CMZ - 11-16-2017 07:09 AM

Using type instead of TYPE even though I am in PPL not CAS doesnt seem to help

Code:

EXPORT STRINGMAGIC()

BEGIN

 PRINT();

 PRINT(IFTE(TYPE(12.5)==DOM_FLOAT-1,STRING('DOM_FLOAT'),"NOT"));

 PRINT(IFTE(TYPE(#12)==DOM_INT-1,STRING('DOM_INT'),"NOT"));

 PRINT(IFTE(TYPE("ST")==DOM_STRING-1,STRING('DOM_STRING'),"OOPS"));

 PRINT(IFTE(TYPE("ST")==3-1,"It IS a THREE, NOT A STRING","OOPS"));

 PRINT(IFTE(TYPE({})==DOM_LIST-1,STRING('DOM_LIST'),"NOT"));

 PRINT(type(12.5)==DOM_FLOAT-1);

 PRINT(type(#12)==DOM_INT-1);

 PRINT(type("ST")==DOM_STRING-1);

 PRINT(IFTE(type("ST")==DOM_STRING-1,"It IS A STRING","NO, IT IS NOT A STRING "+type("M")));

 PRINT(type({})==DOM_LIST-1);

END;

What am I missing?

RE: Can you check for string parameters without a magic number? - Carlos295pz - 11-16-2017 07:28 AM

In Home → TYPE

Code:

Syntax:

TYPE(object)

Returns the type of the object:

 Real

 Integer

 String

 Complex

 Matrix

 Error

 List

 Function

 Unit

?: CAS object. the fractional part is the CAS type

In CAS → type (CAS.type in Home)

Code:

Syntax:

type(Object)

Returns the type of an object.

DOM_int

DOM_FLOAT, float

DOM_INT, integer

DOM_COMPLEX, complex

DOM_IDENT 

DOM_LIST 

DOM_SYMBOLIC, symbol

DOM_RAT, rational

DOM_STRING

DOM_FUNC

The types in Home and CAS are different, they are not related, for example the format #FFh for integers in CAS does not exist

RE: Can you check for string parameters without a magic number? - Carlos295pz - 11-16-2017 07:37 AM

Uso común: TYPE(n)

Code:

EXPORT TypeString(n)

BEGIN

  n:=TYPE(n);

  CASE

    IF n=0 THEN "Real" END

    IF n=1 THEN "Integer" END

    IF n=2 THEN "String" END

    IF n=3 THEN "Complex" END

    IF n=4 THEN "Matrix" END

    IF n=6 THEN "List" END

    IF n=8 THEN "Function" END

    IF n=9 THEN "Unit" END

     "?"

  END

END;

RE: Can you check for string parameters without a magic number? - TravisE - 11-19-2017 03:05 AM

If I understand the OP correctly, they want to compare the types without directly using numeric constants.

(11-16-2017 07:09 AM)StephenG1CMZ Wrote: Using type instead of TYPE even though I am in PPL not CAS doesnt seem to help

Code:

EXPORT STRINGMAGIC() BEGIN PRINT(); PRINT(IFTE(TYPE(12.5)==DOM_FLOAT-1,STRING('DOM_FLOAT'),"NOT")); PRINT(IFTE(TYPE(#12)==DOM_INT-1,STRING('DOM_INT'),"NOT")); PRINT(IFTE(TYPE("ST")==DOM_STRING-1,STRING('DOM_STRING'),"OOPS")); PRINT(IFTE(TYPE("ST")==3-1,"It IS a THREE, NOT A STRING","OOPS")); PRINT(IFTE(TYPE({})==DOM_LIST-1,STRING('DOM_LIST'),"NOT")); PRINT(type(12.5)==DOM_FLOAT-1); PRINT(type(#12)==DOM_INT-1); PRINT(type("ST")==DOM_STRING-1); PRINT(IFTE(type("ST")==DOM_STRING-1,"It IS A STRING","NO, IT IS NOT A STRING "+type("M"))); PRINT(type({})==DOM_LIST-1); END;
What am I missing?

From playing around a bit, it looks like it's necessary to:

1. Call the CAS type function with “CAS.type()”

2. Don't subtract 1 from the DOM_* constants you're comparing to (I'm not sure why you're doing that)

The PPL TYPE() function appears to returns a different set of values, so comparing its return values to the DOM_* constants isn't appropriate. If you really want to avoid using a magic number there, you could either define your own named constants in your program, or you could possibly use something like:

Code:

IF TYPE(SOMEVAR) == TYPE(123.4) // Check for real

…

IF TYPE(SOMEVAR) == TYPE("string") // Check for string

…

etc.

RE: Can you check for string parameters without a magic number? - StephenG1CMZ - 11-19-2017 08:00 AM

(11-19-2017 03:05 AM)TravisE Wrote: If I understand the OP correctly, they want to compare the types without directly using numeric constants.

(11-16-2017 07:09 AM)StephenG1CMZ Wrote: Using type instead of TYPE even though I am in PPL not CAS doesnt seem to help

Code:

EXPORT STRINGMAGIC() BEGIN PRINT(); PRINT(IFTE(TYPE(12.5)==DOM_FLOAT-1,STRING('DOM_FLOAT'),"NOT")); PRINT(IFTE(TYPE(#12)==DOM_INT-1,STRING('DOM_INT'),"NOT")); PRINT(IFTE(TYPE("ST")==DOM_STRING-1,STRING('DOM_STRING'),"OOPS")); PRINT(IFTE(TYPE("ST")==3-1,"It IS a THREE, NOT A STRING","OOPS")); PRINT(IFTE(TYPE({})==DOM_LIST-1,STRING('DOM_LIST'),"NOT")); PRINT(type(12.5)==DOM_FLOAT-1); PRINT(type(#12)==DOM_INT-1); PRINT(type("ST")==DOM_STRING-1); PRINT(IFTE(type("ST")==DOM_STRING-1,"It IS A STRING","NO, IT IS NOT A STRING "+type("M"))); PRINT(type({})==DOM_LIST-1); END;
What am I missing?

From playing around a bit, it looks like it's necessary to:

1. Call the CAS type function with “CAS.type()”

2. Don't subtract 1 from the DOM_* constants you're comparing to (I'm not sure why you're doing that)

The PPL TYPE() function appears to returns a different set of values, so comparing its return values to the DOM_* constants isn't appropriate. If you really want to avoid using a magic number there, you could either define your own named constants in your program, or you could possibly use something like:

Code:

IF TYPE(SOMEVAR) == TYPE(123.4) // Check for real … IF TYPE(SOMEVAR) == TYPE("string") // Check for string …

etc.

Thanks for that tip.
Using IF TYPE(...)==TYPE(1.2) etc. Seems the best way to avoid using constants like 3-1, or even DOM_STRING, which can lead you astray.
To avoid having a 1.2 here and a PI there, which would be distracting, I'd perhaps use
MY_DOM_FLOAT==TYPE(1.2)
IF TYPE(...)==MY_DOM_FLOAT

RE: Can you check for string parameters without a magic number? - Carlos295pz - 11-20-2017 04:38 AM

* In Home

[Image: 38502735732_661645192a_o.png]

Code:

IF TYPE(VAR)=0 THEN ... //REAL

IF TYPE(VAR)=1 THEN ... //INTEGER

IF TYPE(VAR)=2 THEN ... //STRING

IF TYPE(VAR)=6 THEN ... //LIST

* In Home with type (CAS)

[Image: 38534358291_0d5831448e_o.png]

Code:

IF CAS.type(VAR)=1 THEN ... //REAL

IF CAS.type(VAR)=DOM_FLOAT THEN ... //REAL

IF CAS.type(VAR)=12 THEN ... //STRING

IF CAS.type(VAR)=DOM_STRING THEN ... //STRING

IF CAS.type(VAR)=7 THEN ... //LIST

IF CAS.type(VAR)=DOM_LIST THEN ... //LIST