Evaluate a sequence of expressions, "sowing" some to be collected by Reap:

Compute a sum, "sowing" i^2 at each step:

Make separate lists for expressions "sown" with different tags:

Reap only expressions "sown" with tag x:

Sow can be used anywhere in a computation:

It still works inside a function:

A single expression can be "sown" with multiple tags:

If a single tag is repeated, the expression is sown repeatedly:

A pattern in Reap can be used to specify which tags to collect:

The default is the pattern _, so that everything is collected:

Tags can have any form; here they are True and False:

Make a list of all the steps taken in evaluating FindRoot:

Evaluate an iterated map, keeping iterates that are below 1/100:

Find equivalence classes with respect to the value of mod 10:

Sow[x] returns x, "sowing" it as a side effect:

Expressions sown are reaped by the innermost enclosing Reap: