R/valueRangeExpression.R
vreIsSingleValue.RdvreIsSingleValue is a utility function that returns `TRUE` if the
specified value range expression is either numeric, a number expressed as
text or an expression of the form "v=" or "v==".
vreIsSingleValue(vre)
| vre | The value range expression to examine. |
|---|
`TRUE` if vre is a single value, `FALSE` otherwise.