String (and string operations)

Type name: string

Rust type: String

A string is a UTF-8 encoded sequence of characters.

All text content in XMLang is considered a string, and wrapping it in a <string> element is optional, although sometimes it's necessary for, for example, concatenation - it ensures that the value is treated as a single string, rather than multiple children.

All children of a <string> element are evaluated, converted to strings and then concatenated into a single string (without any separators). Null values are ignored.

<string>Hello, world!</string>
<string>42</string>
<string>3.14</string>
<string>true</string>
<string>false</string>
<string />

Conversion to other types

When converting a string to other types, it behaves as follows:

• int: Parses the string as an integer. If the string is not a valid integer, it will throw an error.
• float: Parses the string as a float. If the string is not a valid float, it will throw an error.
• bool: Converts the string to a boolean value, where all values except for the following are considered true:
  • false
  • 0
  • off
  • no
  • empty string

<space />

The <space /> element returns a string with a single space character.

Attributes

• count (int, optional): Specifies the number of space characters to return. Defaults to 1.

Example

<space /> <!-- " " -->
<space count="3" /> <!-- "   " -->

<print>
    <string>Hello,</string>
    <space />
    <string>world!</string>
</print> <!-- prints "Hello, world!" -->

<join>

The <join> element concatenates multiple strings into a single string, with a separator.

Attributes

• separator (string, optional): A string to insert between each child string (default is a single space).
• start (string, optional): A string to prefix the result with (default is an empty string).
• end (string, optional): A string to suffix the result with (default is an empty string).

Children

All its children get evaluated, and then converted to strings before concatenation.

Example

<join end="!">
    <int>1</int>
    <string>Hello</string>
    <string>world</string>
</join> <!-- "1 Hello world!" -->

<trim>

The <trim> element removes leading and trailing whitespace from a string.

Attributes

• start (bool, optional): Whether to trim leading whitespace. Defaults to true.
• end (bool, optional): Whether to trim trailing whitespace. Defaults to true.

Children

It accepts exactly 1 child, which is the string to trim. The child is evaluated and converted to a string before trimming.

Example

<trim>   Hello, world!   </trim> <!-- "Hello, world!" -->
<trim start="true">   Hello, world!   </trim> <!-- "Hello, world!   " -->
<trim end="true">   Hello, world!   </trim> <!-- "   Hello, world!" -->
<trim start="true" end="true">   Hello, world!   </trim> <!-- "Hello, world!" (default) -->
<trim start="false" end="false">   Hello, world!   </trim> <!-- "   Hello, world!   " (why?) -->

<starts-with>

The <starts-with> element checks if a string starts with a given prefix, and returns a boolean value.

Children

It accepts exactly 2 children - the first is the string to check, and the second is the prefix to check against.

Example

<starts-with>
    <string>Hello, world!</string>
    <string>Hello</string>
</starts-with> <!-- true -->
<starts-with>
    <string>Hello, world!</string>
    <string>world</string>
</starts-with> <!-- false -->
<starts-with>
    <string>Hello, world!</string>
    <string>hello</string>
</starts-with> <!-- false (case-sensitive) -->

<ends-with>

The <ends-with> element checks if a string ends with a given suffix, and returns a boolean value.

It is similar to <starts-with>, but checks the end of the string instead.

Children

It also accepts exactly 2 children - the first is the string to check, and the second is the suffix to check against.

Example

<ends-with>
    <string>Hello, world!</string>
    <string>world!</string>
</ends-with> <!-- true -->
<ends-with>
    <string>Hello, world!</string>
    <string>Hello</string>
</ends-with> <!-- false -->
<ends-with>
    <string>Hello, world!</string>
    <string>WORLD!</string>
</ends-with> <!-- false (case-sensitive) -->

<contains>

The <contains> element checks if a string contains a given substring, and returns a boolean value.

It is similar to <starts-with> and <ends-with>, but checks if the string contains the substring anywhere within it.

Children

It accepts exactly 2 children - the first is the string to check, and the second is the substring to check against.

Example

<contains>
    <string>Hello, world!</string>
    <string>world</string>
</contains> <!-- true -->
<contains>
    <string>Hello, world!</string>
    <string>hello</string>
</contains> <!-- false (case-sensitive) -->
<contains>
    <string>Hello, world!</string>
    <string>!</string>
</contains> <!-- true -->