SMIE provides various functions designed specifically for use in the indentation rules function (several of those functions break if used in another context). These functions all start with the prefix smie-rule-.
Return non-nil if the current token is the first on the line.
Return non-nil if the current token is hanging. A token is hanging if it is the last token on the line and if it is preceded by other tokens: a lone token on a line is not hanging.
Return non-nil if the next token is among tokens.
Return non-nil if the previous token is among tokens.
Return non-nil if the current token’s parent is among parents.
Return non-nil if the current token’s parent is actually a sibling. This is the case for example when the parent of a "," is just the previous ",".
Return the proper offset to align the current token with the parent. If non-nil, offset should be an integer giving an additional offset to apply.
Indent current token as a separator.
By separator, we mean here a token whose sole purpose is to separate various elements within some enclosing syntactic construct, and which does not have any semantic significance in itself (i.e., it would typically not exist as a node in an abstract syntax tree).
Such a token is expected to have an associative syntax and be closely tied to its syntactic parent. Typical examples are "," in lists of arguments (enclosed inside parentheses), or ";" in sequences of instructions (enclosed in a {...} or begin...end block).
method should be the method name that was passed to smie-rules-function.
Copyright © 1990-1996, 1998-2019 Free Software Foundation, Inc.
Licensed under the GNU GPL license.
https://www.gnu.org/software/emacs/manual/html_node/elisp/SMIE-Indentation-Helpers.html