Conditional Clauses

The Conditional Clause takes five forms:

1. var [eq,ne]            stringlist
2. var [gt,ge,le,lt]      string
3. var [=,==,!=]          stringlist
4. var [>,>=,<=,<]        string
5. var [numeric,nnumeric]

In cases 1 and 2 we are expecting the varaible to contain string values.

In cases 3 and 4 we are expecting the variable to contain numeric values.

In case 5 we are asking if the varaible is numeric (all numeric digits) or non-numeric (contains a non-numeric digit).

In cases 1 and 3 the comparisons may be to a set of values, and value ranges.

In cases 2 and 4 the comparisons may be only to a single value.

Note the string(s) may evaluate to a variable name.

Examples:

v1 eq v2
v3 gt v4
sex eq M,F
letter eq a,e,i,o,u
letter le m
letter eq a-e,u-z
company eq 'IBM   ','Dell  ','ADM   '

v1 == v2
v3 >  v4
number  = 2,3,5,7,11,13,17,23
number != 0,2,4,6,8
number == 2,4,8,16,32,64,128
age     > 65
age    == 0-17,66-99

salary numeric
salary nnumeric