---------

TERMINAL repo-web-interface

 firefox https://cppget.org
 firefox https://build2.org/pkg/hello

---------

 TERMINAL package-manager-usage

 cd /tmp/
 mkdir hello-gcc5-release
 cd hello-gcc5-release/
 bpkg create cxx config.cxx=g++-5 config.cxx.coptions=-O3
 t

 bpkg add https://build2.org/pkg/1/hello/stable
 bpkg fetch
 bpkg status hello
 bpkg build hello

 bpkg clean hello
 bpkg update hello -v

 bpkg test hello

 t
 hello-1.0.0/hello
 hello-1.0.0/hello CppCon

 bpkg add https://build2.org/pkg/1/hello/testing
 bpkg fetch
 bpkg status libhello
 bpkg build libhello

 bpkg build libhello/1.0.0

 bpkg install config.install.root=/tmp/install hello
 t /tmp/install
 /tmp/install/bin/hello

 bpkg install \
   config.install.root=/tmp/install \
   config.bin.rpath=/tmp/install/lib \
   hello

 /tmp/install/bin/hello

 bpkg uninstall \
   config.install.root=/tmp/install \
   config.bin.rpath=/tmp/install/lib \
   hello

 bpkg help

---------

 TERMINAL windows-package-manager-usage

 # Start VC Native Development Prompt
 cd C:
 cd projects
 mkdir hello-vc14-release
 cd hello-vc14-release\
 bpkg create cxx config.cxx=cl config.cxx.coptions=/O2 -v # config report

 bpkg add https://build2.org/pkg/1/hello/stable
 bpkg fetch
 bpkg build -y hello

 tree /f
 hello-1.0.0\hello.exe CppCon

 bpkg install config.install.root=C:\hello hello

 tree /f C:\hello
 C:\hello\bin\hello.exe

 bpkg uninstall config.install.root=C:\hello hello

---------

 TERMINAL examine-manifest

 What makes a package? Well, it must use the build2 build system.
 Other than that, it should include a manifest file which describes
 the package.

 cat hello-1.0.0/manifest

---------

 TERMINAL build-system-usage

 cd hello0/
 t

 b
 t
 ./hello World

 b clean
 t

 b config.cxx=clang++ -v

 b clean

---------

 TERMINAL persistent-configuration-and-out-of-source-builds

 Two problems: multiple configurations and repeating config.*.

 cd ..
 l     # just hello0

 b 'configure(hello0/@hello0-gcc5-release/)' \
   config.cxx=g++-5 \
   config.cxx.coptions=-O3

 l
 cd hello0-gcc5-release/
 t
 less build/config.build

 b -v            # notice no need to specify config.*
 ./hello World
 b clean

 cd ..
 b 'configure(hello0/@hello0-clang36-release/)' \
   config.cxx=clang++-3.6 \
   config.cxx.coptions=-O3

 l
 b hello0-gcc5-release/ hello0-clang36-release/ -v

---------

 TERMINAL cross-compilation

 x86_64-w64-mingw32-g++ --version

 b 'configure(hello0/@hello0-mingw-release/)' \
   config.cxx=x86_64-w64-mingw32-g++ \
   config.cxx.coptions=-O3 \
   -v

 # Let's talk a bit about what we see.

 cd hello0-mingw-release/
 b -v
 l
 ./hello.exe Windows # What do you think will happen? Everyone understand
                     # how it works?

---------

 TERMINAL cross-compilation-vc

 cd ..
 cl-14

 b 'configure(hello0/@hello0-vc14-release/)' \
   config.cxx=cl-14 \
   config.cxx.coptions=/O2 \
   -v

 # Let's talk a bit about what we see.

 cd hello0-vc14-release/
 b  -v                     # Easiest ever build with VC. And quietest,
                           # if you know what I mean.
 hello.exe VC++

 cd ..
 l

 So here, in 5 minutes, we've setup a build for all the main C++ compiler.

---------

 TERMINAL examine-dot-d

 Want to take a look inside one?

 less hello0-gcc5-release/hello.o.d

---------

 TERMINAL hfb-example-option

 cd hello0
 b configure config.cxx=c++
 b
 b                           # Up-to-date.
 edit build/config.build     # Add -O2
 b -v                        # Recompiled and with -O2.

---------

 TERMINAL hfb-example-compiler

 Let's try something sneakier.

 c++ --version
 sudo update-alternatives --config c++
 c++ --version

 b -v

---------

 TERMINAL hfb-example-override-temporary

 Let's see an example of high fidelity builds and command line overrides.
 Say our hello program dumps core and we want to re-build it with debug
 info so that we can analyze the stack trace.

 b # up-to-date
 b config.cxx.coptions+=-g -v

 Say we fixed our bug and would like to revert to our original
 build. All we have to do is to remove the override:

 b -v

 Note also that this is not some coarse "rebuild everythig if changed
 anything mechanism"; build2 will only update what has been affected
 by the override. For example, if we add a link option there is no
 reason to recompile.

 b config.cxx.loptions=+-L/tmp/lib -v

---------

 TERMINAL hfb-example-override-configuration

 What if we want to add -g permanently. Well, one way is to edit config.build.
 But we can also adjust the configuration from the command line:

 b config.cxx.coptions+=-g configure
 grep coptions build/config.build
 b -v

---------

 TERMINAL install-hello

 b install \
   config.install.root=/opt/hello \
   config.install.sudo=sudo \
   -v

 t /opt/hello
 /opt/hello/bin/hello

 b uninstall \
   config.install.root=/opt/hello \
   config.install.sudo=sudo

---------