Su ayuda con este código

[Armando]

Hola Amigos del foro:

Por favor ayúdenme a entender este simple y sencillo código

Code: Select all  Expand view  RUN

   ? "Texto" <> ""
   ? "Texto" == ""
 

Ambos me devuelven FALSE, y mi lógica me dice que la primera comparación
debería ser TRUE, será que la noche ha sido larga?

Saludos

[cnavarro]

Añade el SET EXACT ON
https://harbour.github.io/doc/clc53.htm ... noeq-ha-op

[Armando]

Cristóbal:

Perfecto, me estaba volviendo loco .

Saludos

[nageswaragunupudi]

Use
? !( "TextTo" == "" )
This does not require changing SET EXACT.
Please note that setting SET EXACT ON will have global effect and somewhere some comparisons may give different results.

[Armando]

Mr. Rao:

Thanks a lot.

Best regards

[Enrico Maria Giordano]

The opposite of

Code: Select all  Expand view  RUN

? "Texto" <> ""

is

Code: Select all  Expand view  RUN

? "Texto" = ""

EMG

[cnavarro]

Use
? !( "TextTo" == "" )
This does not require changing SET EXACT.
Please note that setting SET EXACT ON will have global effect and somewhere some comparisons may give different results.

Dear Rao
Do you mean that what we have to do is induce our code to obtain the result that we expect and that it is not harbour, using the commands and functions that it provides us, that resolves the expression?
So, let's not put the expression (!) and put directly ( ? .T. ) or ( ? .F. ) depending on the result you want to obtain, right? It would be much simpler ( it's a joke ).
The colleague's question is why he obtains that result when the expression is evaluated, I don't think he should be induced as to how it would be resolved to obtain the expected result, that should be done by Harbour.
Use SET EXACT ON and SET EXACT OFF when needed, that's my advice

Quiere decir usted que lo que hay que hacer es inducir a nuestro codigo a obtener el resultado que nosotros esperamos y que no sea harbour, usando los comandos y funciones que nos proporciona, el que resuelva la expresión?
Entonces, no pongamos la expresion (!) y ponga directamente ( ? .T. ) o ( ? .F. ) dependiendo del resultado que usted desea obtener, no?, sería mucho más sencillo ( es una broma ).
La pregunta del compañero es por qué obtiene ese resultado al ser evaluada la expresión, no creo que se le deba inducir a como se resolvería para obtener el resultado esperado, eso debe hacerlo Harbour.
Use SET EXACT ON y SET EXACT OFF cuando se necesite, ese es mi consejo


Armando, por favor, prueba este codigo ( sin el SET EXACT ON )

Code: Select all  Expand view  RUN

? "" <> "Text"
 

[Armando]

Cristóbal:

? "" <> "Text"

Funciona como se espera, retorna (.T.)

Pero
? "Texto" <> ""
No funciona como se espera, retorna (.F.)

Me estoy volviendo loco

Saludos

[Enrico Maria Giordano]

As I wrote, "Text" <> "" is the opposite of "Text" = "", so

Code: Select all  Expand view  RUN

? "Text" <> ""

gives .F. because it is the opposite of

Code: Select all  Expand view  RUN

"Text" = ""

that gives .T. because "Text" begins with "" (any strings contain or begins with ""). Moreover

Code: Select all  Expand view  RUN

"" <> "Text"

gives .T. because it is the opposite of

Code: Select all  Expand view  RUN

"" = "Text"

that gives .F. because "" (the empty string) doesn't begin with "Text".

EMG

[cnavarro]

Enrico, I totally agree with you.