gawk: Requesting Values

1 
1 16.4.8 Requesting Values
1 ------------------------
1 
1 All of the functions that return values from 'gawk' work in the same
1 way.  You pass in an 'awk_valtype_t' value to indicate what kind of
1 value you expect.  If the actual value matches what you requested, the
1 function returns true and fills in the 'awk_value_t' result.  Otherwise,
1 the function returns false, and the 'val_type' member indicates the type
1 of the actual value.  You may then print an error message or reissue the
1 request for the actual value type, as appropriate.  This behavior is
1 summarized in ⇒Table 16.1 table-value-types-returned.
1 
1                                      Type of Actual Value
1 --------------------------------------------------------------------------
1                         String   Strnum   Number   Regex   Array   Undefined
1 -------------------------------------------------------------------------------
1             String      String   String   String   String  false   false
1             Strnum      false    Strnum   Strnum   false   false   false
1             Number      Number   Number   Number   false   false   false
1 Type        Regex       false    false    false    Regex   false   false
1 Requested   Array       false    false    false    false   Array   false
1             Scalar      Scalar   Scalar   Scalar   Scalar  false   false
1             Undefined   String   Strnum   Number   Regex   Array   Undefined
1             Value       false    false    false    false   false   false
1             cookie
1 
1 Table 16.1: API value types returned
1