# MATH introduce numbers (in unary notation)
# Here we count up from zero, go through some primes, etc. There is some
# syntax around the numbers, but that doesn't need to be understood at
# this point. We give numbers in a tweaked unary format, rather than the
# encoding used in the main body of the message.

# MATH introduce equality for unary numbers
# The intro operator does nothing essential, and could be omitted - it just
# tags the first use of a new operator. The = operator is introduced
# alongside a duplication of unary numbers.  The meaning will not quite by
# nailed down until we see other relational operators.

# MATH now introduce other relational operators
# After this lesson, it should be clear what contexts < > and = are
# appropriate in.

# Some random examples

# A few more random examples

# MATH introduce the NOT logical operator

# MATH introduce addition

# MATH introduce subtraction

# MATH introduce multiplication

# MATH introduce non-unary representation of numbers
# Switch from unary numbers to another representation. The representation
# of numbers is now medium-specific (it used to be specified as binary),
# and can be fiddled with without affecting the rest of the message.

# MATH show some syntax variants

# MATH show local assignment

# Scoping and other odd corners.

# Show alternate lookup syntax.

# Now for functions.

# Throw in a little mind-boggle.

# Functions in a box.

# Serve some curry.

# MATH demonstrate existence of memory

# MATH use equality for truth values
# Not quite committing to a *type* for truth values in the message, side-stepping that issue until we really need to decide it.

# MATH show mechanisms for branching

# 'if' does not evaluate branch-not-taken, TODO show this.

# MATH introduce the AND logical operator

# MATH introduce the OR logical operator

# Now is an opportune moment for '<=' and '>='

# MATH illustrate pairs

# MATH introduce mutable objects, and side-effects