Using ryml in your project
Quickstart build samples
These samples show different ways of getting ryml into your application. All the samples use the same quickstart executable source, but are built in different ways, showing several alternatives to integrate ryml into your project. We also encourage you to refer to the quickstart docs, which extensively covers the functionality that you may want out of ryml.
If you’re in a rush to start, try this:
Note
Try the quickstart!
First create this CMakeLists.txt:
cmake_minimum_required(VERSION 3.13)
project(my-quickstart LANGUAGES CXX)
include(FetchContent)
FetchContent_Declare(ryml
GIT_REPOSITORY https://github.com/biojppm/rapidyaml.git
GIT_TAG v0.15.2
)
FetchContent_MakeAvailable(ryml)
add_executable(my-quickstart ${ryml_SOURCE_DIR}/samples/quickstart.cpp)
target_link_libraries(my-quickstart ryml::ryml)
add_custom_target(run my-quickstart
COMMAND $<TARGET_FILE:my-quickstart>
DEPENDS my-quickstart)
Now run the following commands in the same folder:
# configure the project
cmake -S . -B build
# build and run
cmake --build build --target ryml-quickstart -j
# optionally, open in your IDE
cmake --open build
For alternative ways, continue reading this section.
Each sample brings a run.sh script with the sequence of commands
required to successfully build and run the application (this is a bash
script and runs in Linux and MacOS, but it is also possible to run in
Windows via Git Bash or the WSL). Click on the links below to find out
more about each sample:
Sample name |
ryml is part of build? |
cmake file |
commands |
|---|---|---|---|
yes |
|||
yes |
|||
no
needs prior install or package
|
|||
yes
ryml brought as a single
source file + single header
file
|
|||
yes
ryml brought as a single
header, not as a library
|
|||
yes
ryml brought as library
but from the single header
|
|||
yes
ryml brought as a single
header, not as a library
|
|||
yes
ryml brought as library
but from the single header
|
|||
yes
but custom selection of ryml
files: only ints parsing
|
ryml is provided chiefly as a cmake library project, but it can also be used as a single header file, and also as a single source+header file.
There is a tool to amalgamate the code into a single header file. The amalgamated header file is provided with each release, but you can also generate a customized file suiting your particular needs (or commit). See below.
As a library
The single-header or single-source approach is a good way to quickly try the library, but the recommended way is still to use ryml as a library. This is really easy to achieve with cmake and its tooling ecosystem, and you also get better compile times.
As with any other cmake library, you have the option to integrate ryml into your project’s build setup, thereby building ryml together with your project, or – prior to configuring your project – you can have ryml installed either manually or through package managers. See the samples above for different ways to accomplish this.
Currently cmake is required to build ryml; we recommend a recent cmake version, at least 3.13.
As a single-header
The amalgamated header file contains all the function declarations and
definitions. To use it in the project, #include the header at will
in any header or source file in the project, but in one source file,
and only in that one source file, #define the macro
RYML_SINGLE_HDR_DEFINE_NOW before including the header. This
will enable the function definitions. For example:
// foo.h
#include <ryml_all.hpp>
// foo.cpp
// ensure that foo.h is not included before this define!
#define RYML_SINGLE_HDR_DEFINE_NOW
#include <foo.h>
If you wish to package the single header into a shared library, then
you will need to define the preprocessor symbol RYML_SHARED during
compilation.
As a single-source
The amalgamate tool can also be used to create a single source and header pair. This has several advantages over the single-header approach:
It is just as easy to copy into a project (two files instead of one)
Quicker to compile because the header file has less code
Does not require use of the
RYML_SINGLE_HDR_DEFINE_NOW
If you wish to package the single source into a shared library, then
you will need to define the preprocessor symbol RYML_SHARED during
compilation. Further, while building the ryml library you also need to
define RYML_EXPORTS.
Amalgamate tool
There is a tool to amalgamate ryml in tools/amalgamate.py. Note that the tool allows you to select different aspects of the library:
whether to amalgamate into a single-source, or a single-header
whether to amalgamate c4core code
whether to amalgamate fast-float code
whether to amalgamate STL serialization interop
which parse event handlers are to be included in the amalgamated code. This is useful for example when using only the int event parsing (without the ryml tree/node/parse/emit) for a programming language or special application.
Here’s how to use the tool:
[user@host rapidyaml]$ python tools/amalgamate.py -h
usage: amalgamate.py [-h] [--c4core | --no-c4core] [--c4core_dev | --no-c4core_dev]
[--fastfloat | --no-fastfloat] [--stl | --no-stl]
[--engine_hdr | --no-engine_hdr] [-t {single_hdr,single_src}]
[-e {tree,ints,ints_utils,ints_to_testsuite,all,none} [{tree,ints,ints_utils,ints_to_testsuite,all,none} ...]]
[output]
positional arguments:
output output file. defaults to stdout
options:
-h, --help show this help message and exit
--c4core, --no-c4core
amalgamate c4core together with ryml. the default is --c4core
--c4core_dev, --no-c4core_dev
amalgamate c4core (dev utilities) together with ryml. the
default is --no-c4core_dev
--fastfloat, --no-fastfloat
enable fastfloat library. the default is --fastfloat
--stl, --no-stl enable stl interop. the default is --stl
--engine_hdr, --no-engine_hdr
place the parse engine definition header on the header file
when amalgamating as single_src. the default is --no-
engine_hdr
-t, --type {single_hdr,single_src}
Choose amalgamation type. Possible values are - 'single_hdr':
amalgamate everything (all .cpp+.hpp) files into a single .hpp
file. 'single_src': amalgamate all .cpp files into a single
.cpp file, and all .hpp files into a single .hpp file. The
default is single_hdr.
-e, --events {tree,ints,ints_utils,ints_to_testsuite,all,none} [{tree,ints,ints_utils,ints_to_testsuite,all,none} ...]
Specify which event handlers to include. Possible values are -
'tree': (the default) enable the normal ryml event handler to
create the tree, and additionally the Tree, Node, parser and
emitter utilities; if this is not enabled, none of these
components will be included in the amalgamated file. 'ints':
enable the (extra) integer-based event handler. 'ints_utils':
enable the (extra) integer-based event handler utils.
'ints_to_testsuite': enable the (extra) integer events
conversion to testsuite events. 'all': enable all event
handlers. 'none': disable all event handlers. The default is
tree.
From a package manager
ryml is available in most package managers (thanks to all the contributors!) and linux distributions.
Note
These packages are maintained downstream of this repository, so if you have issues with the package, file a report with the respective package maintainer.
Here’s a quick roundup (possibly outdated):
Package managers
Linux distributions:
Arch Linux/Manjaro:
-
dnf install rapidyaml-develdnf install python3-rapidyaml
Although package managers are very useful for getting quickly up to speed, the advised way is still to bring ryml as a submodule of your project, building both together. This makes it easy to track any upstream changes in ryml. Also, ryml is small and quick to build, so there’s not much of a cost for building it with your project.