Sthx::Rule

Performs cursor motion and returns the result, one of Advance::Result: success Advance::Ok or failure Advance::Err.

data is the TreeData object built so far.

To implementors of this method: in case of failure to commit, cursor must be rolled back to its state before calling this method. In other words, advance is implemented in a "transaction" kind of way. Intermediate results and changes must never be available to the caller. This method either succeeds and mutates the cursor; or it fails and leaves the cursor intact.

Applies this rule to the given source string. Returns an application result (see Apply::Result).

• source is the source string to apply this rule on;
• offset specifies the index of the character (not byte!) in the source string where to begin applying this rule.
• exact specifies whether this rule should be expected to consume the source string entirely. If true, any extra characters at the end of the string are treated as an error.
• root is the capture id that should be used for the root of the returned capture tree.

See also: Apply::Ok, Apply::Err, Tree.

Same as #apply? but raises Sthx::SyntaxError instead of returning nil on parse error.

Same as #apply but returns the resulting parse tree, or nil on parse error.