The meson build is across multiple files, you should add together:

  meson.build
  meson_options.txt
  doc/meson.build
  egl/meson.build
  src/meson.build
  tests/meson.build
  cursor/meson.build
  doc/doxygen/meson.build
  doc/publican/meson.build
  doc/doxygen/xml/meson.build
  doc/publican/sources/meson.build
  doc/doxygen/xml/Client/meson.build
  doc/doxygen/xml/Server/meson.build