The motoko sdk grammar doc was autogenerated with no explanation of the symbol meanings, so it’s not very helpful. Is there a guide that explains the grammar/syntax in more detail?
Maybe you are looking for this section? Language quick reference :: Internet Computer
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See the section that @nomeata points to for detailed explanations.
As for the notation used in the auto-generated grammar, it is pretty much standard BNF, with the only addition of optional phrases (...)?.
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Hi Folks
I am trying to build a parser for mo files for an analysis project.
However, what I don’t get is the first two rules, they don’t seem to be part of the standard BNF syntax
e.g. <list(X,SEP)> this looks like a template for a rule, I can’t seem to locate this in the official BNF syntax. I am trying to parse the grammar in ANTLR4 and it seems to not recognize the first two rules which have this syntax. Typically an BNF id is meant to just be a string of chars with ‘-’ or numbers (according to the antlr grammar for BNF this is what an ID is supposed to be made of
id_
: LT ruleid GT
;
ruleid
: ID
;
ID
: (‘a’…‘z’|‘A’…‘Z’) (‘a’…‘z’|‘A’…‘Z’|‘0’…‘9’|‘-’|’ ')+
;
and a rule is
rule_
: lhs ASSIGN rhs
;
where the ASSIGN is ::==
ASSIGN
: ‘::=’
;
So a little lost here, what syntax do the first two rules follow, they almost look like meta-rules. Is the tool that generates them something internal or open source?
Any help will be appreciated, a little lost here…
Regards
Mesbah