string

BAML treats templatized strings as first-class citizens.

Quoted Strings

This is a valid inline string, which is surrounded by double quotes. BAML processes common escape sequences inside quoted strings, including \n, \t, \\, and \".

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"Hello World"
2
3
"\n"
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"a\\b"
5
"a\"b"

Unquoted Strings

BAML also supports simple unquoted in-line strings. The string below is valid! These are useful for simple strings such as configuration options.

1
Hello World

Unquoted strings may not have any of the following since they are reserved characters (note this may change in the future):

• Quotes “double” or ‘single’
• At-signs @
• Curlies
• hashtags #
• Parentheses ()
• Brackets []
• commas ,
• newlines

When in doubt, use a quoted string or a block string, but the VSCode extension will warn you if there is a parsing issue.

Block Strings

If a string is on multiple lines, it must be surrounded by #” and ”#. This is called a block string.

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#"
2
Hello
3
World
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"#

Block strings are automatically dedented and stripped of the first and last newline. This means that the following will render the same thing as above

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#"
2
    Hello
3
    World
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"#

When used for templating, block strings can contain expressions and variables using Jinja syntax.

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template_string Greeting(name: string) #"
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  Hello {{ name }}!
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"#

Escape Characters

Escaped characters are injected as is into the string.

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#"\n"#

This will render as \\n in the output.

Adding a "#

To include a "# in a block string, you can prefix it with a different count of #.

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###"
2
  #"Hello"#
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"###

This will render as #"Hello"#.