System Functions
TBL( ) Convert String Via Table
   
Formats 1. Translation Table in Program: TBL(string$,TBL=tbl_stmtref[,ERR=stmtref])
 
2. Translation Table in Variable: TBL(string$,tbl_var$[,ERR=stmtref])
 
3. Translate Using Position: TBL(position,expr_0[$],expr_1[$] ... ,expr_n[$][,ERR=stmtref])
 
4. Character to Character Conversion : TBL(var$,compare$,table$)
 
Where:
 
  compare$ String table to compare character by character with the value in
    var$. String expression.
  expr_0[$]…n List of expressions to be returned. Numeric or string expressions. Restriction: The expressions must all be the same type (i.e., all characters or all numerics).
  position Determines which expression to use. Positional or numeric expression, range 0 (zero) to n.
  stmtref
    Program line number or statement label to which to transfer control. string$
    Table to use for conversion when a character in the compared value
    matches the value in var$. String expression.
  tbl_stmtref Optional, if your table is embedded in the same statement as the TBL( )function. If you refer to a program tbl_stmtref, it must contain a conversion table.
  tbl_var$ String variable. Contains conversion table to replace elements in the
    string$. String expression.
  var$ String variable. Contains a string to be translated or replaced.
   
Returns Converts string to values in table.
   
Description The TBL( ) function converts a string (all characters or all numeric) to the corresponding values set in a given translation table.
   
See Also Translation Tables in the ProvideX User's Guide
   
Format 1 Translation Table in Program
 
TBL(string$,TBL=tbl_stmtref[,ERR=stmtref])
Use this TBL( ) format if the translation table to convert the string$ is an embedded table in your program. If you include a tbl_stmtref, it must refer to a program statement containing a conversion table defined by a TABLE directive. This statement reference is optional if the conversion table is embedded in the same statement as the TBL( )function. For more information, refer to the TABLE Directive.
   
Format 2 Translation Table in Variable
 
TBL(string$,tbl_var$[,ERR=stmtref])
 
Use this format if the translation table to convert the string$ is in a variable.
   
Format 3 Translate Using Position
 
TBL(position,expr_0[$],expr_1[$] ... ,expr_n[$][,ERR=stmtref])
Use this format to obtain a value based on the numeric value of an expression. The value the TBL( ) function returns depends on the value of position. If it's 0 (zero), then the value of expr_0 will be returned, if 1, then expr_1 will be returned, and so on.
*Note* The values for expr_0[$], expr_1[$], …n[$] can be either string or numeric. The only requirement is the they must be all the same: all string or all numeric.
   
Format 4 Character to Character Conversion

TBL(var$,compare$,table$)

Use this format to do a character-to-character conversion of a string. ProvideX replaces each character in the string variable that matches a character in the first comparison string expression with the corresponding character from the table. That is, when a character in the string variable matches a character in compare$, then:

  • compare$ character 1 is replaced by table$ character 1 in var$,
  • compare$ character 2 is replaced by table$ character 2 in var$,
  • compare$ character 3 is replaced by table$ character 3 in var$,
  • ... and so on.

For example:

X$ = TBL(X$, "abc","ABC")

The above would replace all lower a,b, or c's with A, B, or C respectively.
   
Examples Example 1:

->T$="W"
->P$=TBL(POS(T$="DWM"),"???","Daily","Weekly","Monthly")
->PRINT P$
Weekly

In the above example the value in T$ is passed to a POS function to determine where in the string "DWM" it occurs. The POS function will return 1,2 or 3 based on which character it matches, or 0 if none. This value is then processed by the TBL function to return "???" for zero, or the appropriate text.

Example 2:

PRINT "Expires:",TBL(EXP_DT$="",EXP_DT$,"Never")

If EXP_DT$is null, the logical expression EXP_DT$=" " yields 1. A null date will print "Never". Otherwise, it yields 0 (zero) and the value of EXP_DT$ is printed. In effect, this form of TBL( ) becomes: TBL(logical_expr, else_value,true_value).

Example 3:

string$="ABCDEFG 123"
newstring$=tbl(string$,"ACF ","123_") ! newstring$ is "1B2DE3G_123"

This format of the TBL function replaces each character found in "ACF " with its corresponding character in "123_"