Alt text between the brackets, or undefined when the brackets are empty
End offset (exclusive) just past the closing parenthesis
The href exactly as written in the source
Start offset of the leading ! in the surrounding content
Link title exactly as written, or undefined when absent
A markdown image link occurrence with its exact span in the source content.
The span covers the whole
expression so callers can rewrite the occurrence surgically without re-serialising the surrounding document.