Package nativereg is the metadata a native coin does not have.
gno.land/r/moul/x/nativereg/v0The metadata a native coin does not have.
/gno.land/r/moul/x/moultest/v0:moultest is the entire object. The chain stores a
string and a balance: no name, no symbol, no decimals, no icon, no link to the
issuer. A wallet showing you that balance has only the path to print.
This realm is where a denom says what it is. It is the mirror of
r/nt/grc20reg, and the two solve opposite
problems: a GRC20 carries its own name and is hard to find, so that registry
maps a key to an object; a native denom is trivial to find and carries no
name, so this one maps the denom to what it means.
A denom embeds the package path of the realm allowed to issue it, verbatim:
"/" + pkgPath + ":" + baseName. So the issuer is readable from the string, and
Register simply requires the caller to be it. No allowlist, no owner, no
signature scheme.
1import "gno.land/r/moul/x/nativereg/v0"
2
3func init(cur realm) {
4 nativereg.Register(cross(cur), Denom, "My Coin", "MINE", 6,
5 "one line about what it is for")
6}
A user account cannot register anything, not even a denom it holds every unit of: there is no package path in a user call to compare against. What is being described is the issuance, not the holding.
IssuerOf(denom) answers the same question for a denom nobody ever registered,
which is the case that matters: given a balance you did not ask for, that is how
you find the code that can take it away.
Denom and Issuer are facts, because the chain enforces the relation between
them. Everything else is whatever the issuing realm chose to say, and Decimals
in particular is a display hint with nothing behind it: the bank has no notion
of divisibility, so a coin wrapped out of a 6-decimal GRC20 is still counted in
whole units by every balance query.
Trusting an entry means trusting the realm that wrote it, exactly as much as
holding its coin already means trusting it not to call RemoveCoin on you.
?<denom> shows one entry, ?<pkgpath> shows everything one realm issues.
Part of moul/gno-contracts — moul's versioned gno.land contracts. See the repository for the full catalog, build/test tooling, and usage.
Dependency graph:
🧪 Highly experimental — potentially vibe-coded. Not audited; may break, change, or be removed at any time. Do not use with anything of value. Full disclaimer: DISCLAIMER.
Package nativereg is the metadata a native coin does not have.
A realm-issued coin is a string and a balance. `/gno.land/r/moul/x/moultest/v0:moultest` is the entire object: no name, no symbol, no decimals, no icon, no link to whoever issues it. The bank knows the number and nothing else, so a wallet or an explorer showing you a balance has only that path to print.
This realm is where a denom says what it is. It is the mirror image of `r/nt/grc20reg`, and the two solve opposite problems: a GRC20 is an object that carries its own name and is hard to FIND, so the registry maps a key to the object; a native denom is trivial to find and carries no name, so the registry maps the denom to what it means.
A denom embeds the package path of the realm allowed to issue it, verbatim: `"/" + pkgPath + ":" + baseName` (`chain.CoinDenom`). So the issuer is readable from the denom, and Register simply requires the caller to be it. A realm registers its own coins and nobody else's, with no allowlist, no owner and no signature scheme.
A user account cannot register anything, not even a denom it holds all of: there is no package path in a user call to compare against. That is the intended shape, since the thing being described is the issuance, not the holding.
`Denom` and `Issuer` are facts: the chain enforces the relation between them. Everything else is whatever the issuing realm chose to say, and `Decimals` in particular is a DISPLAY hint with nothing behind it. The bank has no notion of divisibility; a coin wrapped out of a 6-decimal GRC20 is still counted in whole units by every balance query. Rendering 1000000 as 1.000000 is a convention between this realm and whoever reads it.
So trusting an entry means trusting the realm that wrote it, exactly as much as holding its coin already means trusting it not to call `RemoveCoin` on you.
1const (
2 // MaxName, MaxSymbol and MaxDoc bound what an issuer can store here. The
3 // registry pays the storage for every byte a caller hands it, so the
4 // limits are the realm's own cost control, not a style rule.
5 MaxName = 40
6 MaxSymbol = 12
7 MaxDoc = 200
8 // MaxDecimals matches the GRC20 ceiling, which is where a wrapped coin's
9 // hint comes from in practice.
10 MaxDecimals = 18
11)Count returns how many denoms are registered.
IsRegistered reports whether a denom has said anything about itself.
IssuerOf returns the package path embedded in a denom, without consulting the registry: the relation is in the string itself. It aborts on anything that is not a realm denom, which includes `ugnot`.
It is exported because it is useful to anybody handling a denom, registered or not: given a balance, this is how you find the code that can take it away.
Register records or rewrites what a denom means. The caller must be the realm the denom names, which is the entire authorization.
Calling it again overwrites the entry and bumps [Entry.Revisions]. An issuer can always re-describe its own coin, and can never describe anybody else's.
Render lists the registry. `?<denom>` shows one entry, `?<pkgpath>` shows everything one realm issues.
ByIssuer returns every entry issued by one realm, in registration order.
Get returns the entry for a denom, and whether it has one.
List returns every entry, in registration order.
MustGet is Get for a caller that treats an unregistered denom as a bug.
1type Entry struct {
2 // Denom is the full chain denom, the key of this registry.
3 Denom string
4 // Issuer is the package path embedded in Denom: the only realm that can
5 // issue, remove or re-describe this coin.
6 Issuer string
7 // Name, Symbol and Decimals are display metadata, chosen by the issuer.
8 // Decimals is a hint; see the package doc.
9 Name string
10 Symbol string
11 Decimals int
12 // Doc is one line about what the coin is for.
13 Doc string
14 // Height is when the entry was last written.
15 Height int64
16 // Revisions counts how many times the issuer has rewritten it.
17 Revisions int
18}Entry is what one denom says about itself.
