F_IS_COMPARISON_OPERATOR

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// Function Name : f_is_comparison_operator
// Argument Name : as_source, Arg Type : String, Pass By : Value
// Return Type :      Boolean
///////////////////////////////////////////////////////////////////////////////////////////////////////////////
//    Description:   Determines whether a string contains only Comparison
//                        Operator characters.
///////////////////////////////////////////////////////////////////////////////////////////////////////////////

Long        ll_count=0
Long        ll_length
Char        lc_char[]
Integer     li_ascii

//Check parameters
If IsNull(as_source) Then
    boolean lb_null
    SetNull(lb_null)
    Return lb_null
End If

//Get the length
ll_length = Len (as_source)

//Check for at least one character
If ll_length = 0 Then
    Return False
End If

//Move string into array of chars
lc_char = as_source

//Perform loop around all characters
//Quit loop if Non Operator character is found
Do While ll_count < ll_length
    ll_count ++
   
    //Get ASC code of character.
    li_ascii = Asc (lc_char[ll_count])
   
    If li_ascii=60 or            /* < less than */     &
        li_ascii=61 or            /* = equal */         &
        li_ascii=62 Then        /* > greater than */
        //Character is an Comparison Operator.
        //Continue with the next character.
    Else
        Return False
    End If
Loop
   
// Entire string is made of Comparison Operators.
Return True