Groups more than one expression into a single expression. The value of the block function is the value of its last argument.
The <set> function does not return a value. If the last line in a block statement involves a set operation, the block statement will not return a value. If you want the block statement to return the value of a variable, use <ref>variable_name</ref> on the last line of the block statement.
<block> <s>Hello there!</s> <add> <i>100</i> <i>2</i> </add> <i>42</i> </block>
The block returns a value of 42, the value of its last argument.
For an example of using block with a trace statement, see Debugging and Testing Expressions.