Recent changes to Configuration

Configuration modified by Jussi Pakkanen

Jussi Pakkanen — Thu, 04 Sep 2014 07:57:55 -0000

--- v7
+++ v8
@@ -1,3 +1,10 @@
+The Meson build system has moved
+==
+
+The new home of Meson's documentation is [here](https://github.com/jpakkane/meson/wiki). The information below is preserved only for posterity. It should be considered out of date.
+
+-------
+
 Configuration files

 If there are multiple configuration options, passing them through compiler flags becomes very burdensome. It also makes the configuration settings hard to inspect. To make things easier, Meson supports the generation of configure files. This feature is similar to one found in other build systems such as CMake.

Configuration modified by Jussi Pakkanen

Jussi Pakkanen — Sun, 02 Jun 2013 22:23:55 -0000

--- v6
+++ v7
@@ -16,7 +16,7 @@

     #define VERSION_STR "1.2.3"

-More specifically, Meson will find all strings of the type @varname@ and replace them with respective values set in conf_data. You can use a single configuration_data object as many times as you like, but it becomes immutable after the first use. That is, after it has been used once, the set function becomes unusable and trying to call it causes an error.
+More specifically, Meson will find all strings of the type @varname@ and replace them with respective values set in conf_data. You can use a single configuration_data object as many times as you like, but it becomes immutable after the first use. That is, after it has been used once the set function becomes unusable and trying to call it causes an error.

 For more complex configuration file generation Meson provides a second form. To use it, put a line like this in your configuration file.

Configuration modified by Jussi Pakkanen

Jussi Pakkanen — Sun, 02 Jun 2013 22:23:05 -0000

--- v5
+++ v6
@@ -29,7 +29,9 @@
     #define TOKEN 4   // If TOKEN is set to an integer or string value.
     /* undef TOKEN */ // If TOKEN has not been set to any value.

-Note that if you want to define a C string, you need to do the quoting yourself, like this conf.set(TOKEN, '"value"').
+Note that if you want to define a C string, you need to do the quoting yourself like this:
+
+    conf.set(TOKEN, '"value"')

 Often you have a boolean value in Meson but need to define the C/C++ token as 0 or 1. Meson provides a convenience function for this use case.

Configuration modified by Jussi Pakkanen

Jussi Pakkanen — Sun, 02 Jun 2013 21:07:27 -0000

--- v4
+++ v5
@@ -22,12 +22,14 @@

     #mesondefine TOKEN

-The replacement that happens depends on what the value of TOKEN is:
+The replacement that happens depends on what the value and type of TOKEN is:

     #define TOKEN     // If TOKEN is set to boolean true.
     #undef TOKEN      // If TOKEN is set to boolean false.
-    #define TOKEN 4   // If TOKEN is set to an integer value.
+    #define TOKEN 4   // If TOKEN is set to an integer or string value.
     /* undef TOKEN */ // If TOKEN has not been set to any value.
+
+Note that if you want to define a C string, you need to do the quoting yourself, like this conf.set(TOKEN, '"value"').

 Often you have a boolean value in Meson but need to define the C/C++ token as 0 or 1. Meson provides a convenience function for this use case.

Configuration modified by Jussi Pakkanen

Jussi Pakkanen — Sun, 02 Jun 2013 13:17:04 -0000

--- v3
+++ v4
@@ -29,7 +29,7 @@
     #define TOKEN 4   // If TOKEN is set to an integer value.
     /* undef TOKEN */ // If TOKEN has not been set to any value.

-In several cases you have a boolean value in Meson but need to define the C/C++ token 0 or 1. Meson provides a convenience function.
+Often you have a boolean value in Meson but need to define the C/C++ token as 0 or 1. Meson provides a convenience function for this use case.

     conf.set10(token, boolean_value)
     # The line above is equivalent to this:

Configuration modified by Jussi Pakkanen

Jussi Pakkanen — Sun, 02 Jun 2013 13:12:26 -0000

--- v2
+++ v3
@@ -18,6 +18,27 @@

 More specifically, Meson will find all strings of the type @varname@ and replace them with respective values set in conf_data. You can use a single configuration_data object as many times as you like, but it becomes immutable after the first use. That is, after it has been used once, the set function becomes unusable and trying to call it causes an error.

+For more complex configuration file generation Meson provides a second form. To use it, put a line like this in your configuration file.
+
+    #mesondefine TOKEN
+
+The replacement that happens depends on what the value of TOKEN is:
+
+    #define TOKEN     // If TOKEN is set to boolean true.
+    #undef TOKEN      // If TOKEN is set to boolean false.
+    #define TOKEN 4   // If TOKEN is set to an integer value.
+    /* undef TOKEN */ // If TOKEN has not been set to any value.
+
+In several cases you have a boolean value in Meson but need to define the C/C++ token 0 or 1. Meson provides a convenience function.
+
+    conf.set10(token, boolean_value)
+    # The line above is equivalent to this:
+    if boolean_value
+      conf.set(token, 1)
+    else
+      conf.set(token, 0)
+    endif
+
 ---

 [Back to index](Manual).

Configuration modified by Jussi Pakkanen

Jussi Pakkanen — Fri, 24 May 2013 19:27:13 -0000

--- v1
+++ v2
@@ -4,18 +4,19 @@

 Suppose we have the following Meson snippet:

-version = '1.2.3'
-configure_file('config.h.in', 'config.h')
+    conf_data = configuration_data()
+    conf_data.set('version', '1.2.3')
+    configure_file(input : 'config.h.in', output : 'config.h', configuration : conf_data)

 and that the contents of config.h.in are

-#define VERSION_STR "@version@"
+    #define VERSION_STR "@version@"

 Meson will then create a file called config.h in the corresponding build directory whose contents are the following.

-#define VERSION_STR "1.2.3"
+    #define VERSION_STR "1.2.3"

-More specifically, Meson will find all strings of the type @varname@ and replace them with respective variable values.
+More specifically, Meson will find all strings of the type @varname@ and replace them with respective values set in conf_data. You can use a single configuration_data object as many times as you like, but it becomes immutable after the first use. That is, after it has been used once, the set function becomes unusable and trying to call it causes an error.

 ---

WikiPage Configuration modified by Jussi Pakkanen

Jussi Pakkanen — Thu, 28 Feb 2013 22:49:06 -0000

Configuration files

If there are multiple configuration options, passing them through compiler flags becomes very burdensome. It also makes the configuration settings hard to inspect. To make things easier, Meson supports the generation of configure files. This feature is similar to one found in other build systems such as CMake.

Suppose we have the following Meson snippet:

version = '1.2.3' configure_file('config.h.in', 'config.h')

and that the contents of config.h.in are

#define VERSION_STR "@version@"

Meson will then create a file called config.h in the corresponding build directory whose contents are the following.

#define VERSION_STR "1.2.3"

More specifically, Meson will find all strings of the type @varname@ and replace them with respective variable values.

Back to index.