SyntaxWML

Wesnoth syntax has two basic elements: tags and attributes. Further, attributes consist of keys and values. Tag names and keys cannot contain whitespace. Any line beginning with a pound (#) sign is considered by WML as a comment, except for preprocessor declarations beginning with #.

[tag-name//] data is a tag.

 Tags are used to partition information.
 A top level tag is one that is not inside any other tag.
 Each top level tag describes something about the game.
 Different tags work differently.
 For information about how a certain tag works, see ReferenceWML.

[+tag-name//] data [1] means that data

 will be considered as part of the data for the most recent [tagname]
 tag.  The data of [+//tag-name] will be considered as coming after
 all data in [tag-name//], so attributes of [+//tagname] will replace
 attributes of the original [tagname].

key//=//value newline// is an attribute, or an assignment

 of a value to a key.  When this line is processed, the value of key
 for the tag that the attribute is in is set or changed to value.
 All text from '=' until the end of the line is considered to be part
 of value//.  Note that key is not a WML variable (with the
 exception of VariablesWML); the value it is set to has a use which
 is determined by C++ code, not WML code.
 In order to change the value of a WML variable,
 you need to use [set_variable] (see InternalActionsWML).
 There should be no space between the key and the '=' symbol!
 If there is whitespace, the attribute assignment is ignored.

key1//,//key(s)2//=//value1//,//value(s)2 newline is the same as

 key1//=//value1 newline key(s)2//=//value(s)2 newline.
 If there are extra keys, they will be set to an empty value.
 If there are extra values the last key will be set to the comma
 separated list of all remaining values.

Although a value can be just text corresponding to a function of its key (these values are displayed in quotes ('') in ReferenceWML), a value can also be encoded:

"multiple-line-value" a multiple-line value must be enclosed in

 quotes, to prevent it being interpreted as a single-line value.
 Note that multiple-line-value doesn't have to have multiple lines;
 it can simply be a single-line value enclosed in quotes for clarity.

_ "text//" is a translatable value.

 text is English (US) text that will be displayed in-game at
 some point.  Gettext (see GetText) is used to determine what to
 display if English (US) is not the current language.

value-1 + value-2 can be used to concatenate two

 different strings.  If you want to have a value that actually
 has a plus sign (+) in it, you need to enclose the string
 containing the + character in quotes
 (see "multiple-line-value" above).

$variable-name// a variable value depends on the value of

 the WML variable variable-name.  See VariablesWML for
 more information on WML-variable based values.

Example:

[scenario]
id=Elves Besieged
        [side]
        side,gold=1,100
        [/side]
        [+side]
        recruit=Elvish Fighter,Elvish Archer
        [/side]
[/scenario]

In this example, [scenario] is a top level tag. When these lines are read, WML will know that there is a scenario with the ID "Elves Besieged". Later, when WML is told to play that scenario, it will read the [side] tag and give 100 gold to side 1. Then it will read the [+side] tag. It interprets this tag as belonging to side 1, since the most recent [side] belonged to side 1. So the [+side] tag allows side 1 to recruit Elvish Fighters and Elvish Archers. (Then it will crash, as the leader of side 1 has no unit type. But this isn't really important.)

Notes: Normally the order and indentation of attributes and tags does not matter, as long as the levels within tags are not changed. So the above example could have been written:

[scenario]
[side]
gold=100
side=1
[/side]
id=Elves Besieged
[/scenario]

Data inside tags should be separated with tabbing; see ConventionsWML.

SyntaxWML

See Also