!code [iso]
!no_preamble [tex]
# Uncomment the following line for LaTeX 2.09
# !tex \documentstyle[12pt]{article}
# Uncomment the following lines for LaTeX2e
!tex_2e
!raw [tex] \documentclass[12pt,a4paper]{article}
!raw [tex] \usepackage{a4}
!begin_document
!node Example
This example uses a userdefined (!LaTeX) preamble.
!end_document
!ifdest [tex] !define ab2 $(a+b)^2 = a^2 + 2ab + b^2$ !else !macro ab2 (a + b)^2 = a^2 + 2ab + b^2 !endif ... The first binomial theorem: (!ab2)