GNU gcc and g++, GNU make, libncurses or libcurses.

GNU gcc and g++, GNU make, libncurses or libcurses. You need the
development headers for ncurses - they may not be installed by default
on some Unixes.

flex and bison are optional but highly recommended. Recent versions of byacc are
also fine.

flex and bison are optional but highly recommended. Recent versions of
byacc are also fine (edit your makefile appropriately).

(NOTE: The level compiler is not in its final form yet; these instructions are
likely to change for future releases.)

Crawl uses a level compiler to convert the human-readable level design (.des)
files in the source/dat directory into code that's compiled into Crawl.

Crawl uses a level compiler to read the level design (.des) files in
the source/dat directory.

If you're using one of the standard makefiles, the steps described in this
section are performed automatically:

If you're using one of the standard makefiles, the steps described in
this section are performed automatically:

* Compile the resulting C++ source files with mapdef.cc (in the main source
  directory) and levcomp.cc to produce the levcomp executable.
Once you've built the level compiler, run it on the .des files in source/dat and
append the results to mapdefs.ixx:
levcomp(.exe) mapdefs.ixx < dat/vaults.des
levcomp(.exe) -a mapdefs.ixx < dat/splev.des
(the -a option tells levcomp to append to mapdefs.ixx instead of overwriting the
existing contents.)

* Compile the resulting C++ source files and levcomp.cc and link the
  object files into the Crawl executable.

When mapdefs.ixx is built, Crawl can be compiled as before. mapdefs.ixx is
#included in maps.cc.

intermediate files are provided under source/prebuilt. The makefiles provided
with the Crawl source distribution will use these pre-generated files
automatically if flex/bison is not available.
If you're using an Integrated Development Environment and don't want to modify
the level design files at all, a pre-generated mapdefs.ixx is provided in
source/prebuilt - you can add source/prebuilt as an include directory and build
Crawl as before. (This is not necessary if you're using Xcode on OS X
- the Xcode project provided with the source distribution is aware of the level
compiler and will build and use it automatically.)

intermediate files are provided under source/prebuilt. The makefiles
provided with the Crawl source distribution will use these
pre-generated files automatically if flex/bison is not available.

This also depends on how you install Lua - some package management
systems build just the plain old liblua.so even for pre 5.1 Lua. If in
doubt, try both "-llua -llualib" and "-llua".

On many Linuxes, the package management system installs Lua libraries
including the version number, so the linker option becomes something
like:

LIB = -llua50