Horizontal

Turn a definition based on multiple productions into a top choice-based one.

The action is a reverse of vertical.

Syntax

horizontal:
        nonterminal::nonterminal

Example

If some or all of the original production rules are labelled:

[onedec] decs:
        dec
[moredecs] decs:
        dec decs

then, after using this transformation:

horizontal(decs);

each label is converted to a selector in a corresponding place:

decs:
        onedec::dec
        moredecs::(dec decs)

Relevant files

• shared/prolog/xbgf1.pro
• shared/rascal/src/transform/library/Disjunction.rsc
• shared/xsd/xbgf.xsd

See also

• Horizontal is a part of XBGF

Contributors

• Ralf Lämmel (@rlaemmel)
• Vadim Zaytsev (@grammarware)