Verbs and Built-in Functions › &TYPECHK

&TYPECHK

Returns one of a supplied list of data types based on supplied variables.

&TYPECHK (type1, type2 ....) &var1 [ &var2 .... &varn ]

Allows you to test one or more variables against a list of type attributes.

&TYPECHK is a built-in function and must be used to the right of an assignment statement. The statement returns a value after assignment that represents the first matching type attribute that was found or else a null value.

The first supplied value is tested against each of the type values specified in the list until a match is found. If the variable's type attribute does not match any in the list, then a null value is returned. If a match is found, then that type is returned.

If more than one source value is supplied, then &TYPECHK produces one of the following results:

• If all values match the type of the first value, then that type is returned.
• If any of the values have a different type attribute from the first value, then a null value is returned.

Operands:

type

One or more type values against which the source values are to be tested. A single type value is coded on its own, or multiple values is coded enclosed in parentheses. Valid values and value meanings for type are:

• ALPHA, an alphabetic character value
• ALPHANUM, an alphanumeric character value
• ALPHANUMNAT, an alphanumeric or national character value
• DATE1, a date in the format of &DATE1 system variable
• DATE2, a date in the format of &DATE2 system variable
• DATE3, a date in the format of &DATE3 system variable
• DATE4, a date in the format of &DATE4 system variable
• DATE5, a date in the format of &DATE5 system variable
• DATE6, a date in the format of &DATE6 system variable
• DATE7, a date in the format of &DATE7 system variable
• DATE8, a date in the format of &DATE8 system variable &TYPECHK
• DATE9, a date in the format of &DATE9 system variable
• DATE10, a date in the format of &DATE10 system variable
• DATE11, a date in the format of &DATE11 system variable
• DATE12, a date in the format of &DATE12 system variable
• DATE13, a date in the format of &DATE13 system variable
• DATE14, a date in the format of &DATE14 system variable
• DATE16, a date in the format of &DATE16 system variable
• DATE17, a date in the format of &DATE17 system variable
• DOMAIN, a valid NCL domain ID
• DSN, a valid data set name (with or without member name in z/OS)
• HEX, a hexadecimal value
• IPADDR, a valid IP address, in the format A.B.C.D, where each of A, B, C, and D have a valid range of 0 to 255
• MIXED, a string containing valid DBCS data
• MSGLVL, a valid AOM message level value
• NAME, a valid PDS member name (that is, starts with an alphabetic or national character and all other characters are alphanumeric or national characters)
• NAME12, a variable, up to 12 characters, conforming to member name rules
• NAME256, a variable, up to 256 characters, conforming to member name rules
• NULL, a null value
• NUM, a numeric value
• REAL, a real number
• ROUTCDE, a valid AOM message route code
• SIGNNUM, a signed number in the range -2,147,483,647 to +2,147,483,647
• TIME1, a time value with the format of the &ZTIME1 system variable
• TIME2, a time value with the format of the &ZTIME2 system variable
• TIME3, a time value with the format of the &ZTIME3 system variable
• Y, Y or YES
• N, N or NO

&var

This operand is a system or user variable. Multiple variables is coded.

Examples: &TYPECHK

&1 = ABC
&A = &TYPECHK (NUM,ALPHA) &1

Result: &A = ALPHA

&1 = +111
&A = &TYPECHK (NUM,SIGNNUM) &1

Result: &A = SIGNNUM

&1 = 1234567890
&A = &TYPECHK (SIGNNUM,NUM) &1

Result: &A = SIGNNUM

&1 = 12345678901
&A = &TYPECHK (SIGNNUM,NUM) &1

Result: &A = NUM (Because the number exceeds the maximum for NCL arithmetic).

&1 = 123 
&2 = ABC  
&A = &TYPECHK (NUM,HEX) &1 &2

Result: &A is set to NULL, because &1 and NUM match but NUM does not match &2.

Notes:

By using &TYPECHK to test variables before using them in arithmetic functions, you can avoid the procedure being terminated with an invalid arithmetic function error condition due to invalid input.

The NUM type applies to variables containing a number with no leading sign. This number can, however, be too large for arithmetic operations. To determine whether you can use a numeric variable in arithmetic, check its type attribute for SIGNNUM or REAL. SIGNNUM is returned if the number is a positive or negative integer that is used in arithmetic.

ALPHA means that the variable contains alphabetic characters only, and no national characters. ALPHANUM means that the variable can contain alpha and numeric characters, but not necessarily a mixture.

When working with full-screen procedures, Panel Services provides facilities that automatically perform validation of data entered by the operator.

Note: For more information, see the Network Control Language Programming Guide.

If &TYPECHK is used to test a list of variables which include NULL values, then NCL variable substitution logic does not let it recognize the existence of those null variables.