11
votes
Accepted
What does @ prefix means?
It means type application.
In this case, the function is polymorphic with the following type:
logInfo :: forall a effs. Member (LogMsg a) effs => a -> Eff effs ()
by using TypeApplications ...
- 497
5
votes
What are the benefits of using Plutarch?
This is covered pretty nicely in the project README. https://github.com/Plutonomicon/plutarch#why-plutarch
In short, Plutus Tx attempts to replicate Haskell-like lazy semantics inside of Untyped ...
- 106
4
votes
Accepted
Couldn't match expected type ‘BuiltinData’ in locally run playground
The local playground code is compiled to a version that is too recent for week 2. It needs to be compile to the correct commit for week 2. The change to BuiltinData only happened at week 04.
Check the ...
- 480
4
votes
Accepted
What exactly is the script context in Plutus context?
The context includes two parts: TxInfo and ScriptPurpose.
data ScriptContext = ScriptContext{
scriptContextTxInfo :: TxInfo,
scriptContextPurpose :: ScriptPurpose
}
When people are talking ...
- 3,232
3
votes
Accepted
Understand purpose of tx-out-datum-hash in Lars' lobster NFT minting example
That value is the hash value of an empty list. You can calculate it in the repl as follows:
import Ledger qualified
import PlutusTx qualified
emptyListDatum = Ledger.Datum $ PlutusTx.toBuiltinData ([]...
- 1,294
3
votes
Accepted
Is it possible to not compile data constructors with plutus-tx?
I think you must be using the datatype in some way if you're doing anything with this type.
However, perhaps you just don't care about the Nat index. It would be nice to be able to ignore this, but ...
- 46
3
votes
Accepted
Is it possible to have an On-chain Set data structure?
Any type that works with PlutusTx.unstableMakeIsData (or its equivalent) should work, since Datum & Redeemer are wrappers for BuiltInData which is a "wrapper" for Data.
EDIT:
I tried the ...
- 815
3
votes
What exactly is the script context in Plutus context?
Aiming to contribute to the great answer from Mitchell, I'll add this:
Script context can be understood like the summary of the transaction and can be used to validate it. This includes all inputs ...
- 1,754
2
votes
Writing basic validator scripts
Although there may have been changes, this remains a valid question.
The code shown in the question is the boilerplate code that accompanies a validator implementation for on-chain execution. A simple ...
- 480
2
votes
Accepted
Are Validators pretending transaction already completed?
Yes, a validator is called prior to the start of the transaction as it part of the constraints that determines if the transaction can proceed. A validator that executes on-chain has no visibility of ...
- 480
2
votes
Constraints.mustPayToPubKey requires txSignedBy?
Does the validator need to check that the transaction sees that pkh?
Yes. There is more than one way to organize the logic though.
Whichever way you structure the lottery, I will assume that the ...
- 3,232
2
votes
(Lecture #6 It #2 - Core.Hs) : Explaining lookups use of both typedValidatorLookups and otherScript?
This one is a bit technical it has to do with looking up and updating the constraints of an already existing transaction (that belongs to the script address). See Case ii) to skip my synopsis.
Just a ...
- 488
2
votes
Accepted
How does `submitTxConstraintsWith` make usage of the ScriptLookups?
The family of submitTx functions all create transactions from the constraints submitted in the arguments. The most general implementation of the function is
submitTxConstraintsWith
:: ScriptLookups ...
- 480
2
votes
String in Datum
Not really sure what you mean by "end user to see the datum in the script" and how having a Text or String in the datum would make any difference to this. Datums are not easily visible to ...
- 558
2
votes
How to calculate fees for Plutus Smart Contract?
You can now use fee estimator at https://testnets.cardano.org/en/testnets/cardano/tools/plutus-fee-estimator/
- 146
2
votes
How can I secure a Datum value in a smart contract?
There are multiple ways to do that.
Option 1:
If you have "script-wide" constants, like your mentioned example of an auction house fee, I suggest parameterizing your contract like it is done ...
- 1,162
2
votes
Accepted
Confusion regarding findOwnInput function with on-chain code
Calling findOwnInput in a validator returns the value contained in the Script-UTxO that is currently being validated. In your example above it is the one with 2 Ada in it.
Your example above is, ...
- 1,549
2
votes
How to get a base 16 hex BuiltinString from getTxId
I was able to resolve this issue by converting (encoding) the BuiltinByteString from getTxId into a hex format. From there I was able to inpsect the hex digits. Below is an onchain encodeHex ...
- 297
2
votes
Unclear error during Plutus ScriptContext construction (force headList [])
The problem was that I was mixing on-chain code written in Plutus V1 with off-chain code that expects Plutus V2. In particular, the off-chain code utilities in the hydra-cardano-api library assume ...
1
vote
Submit transactions to the blockchain in Plutus
the original vision was to use Plutus Application Backends, unfortunately the development is lagging behind.
We're still early in the development ecosystem, so what you described is mostly the one we ...
1
vote
Accepted
cardano-serialization-lib ExUnits
These two are the maximum computation resources you're declaring your contract needs. I believe the easiest way to get the "right" value, is to interact with your contract on testnet in ...
- 76
1
vote
How expressive & secure is the Plutarch eDSL?
I'm approaching the tool so I would not consider myself a Plutarch expert
however to my understanding, Plutarch is designed to be compatible with the entire PlutusTx API
since the real code of smart ...
- 992
1
vote
can't understand which part of the code is not "PlutusTx"
The name wrappedMintingPolicy in the where statement is not indicated with the INLINABLE pragma. Maybe adding the line
{-# INLINEABLE wrappedMintingPolicy #-}
solves the problem.
- 56
1
vote
Difference between `PlutusTx.TH.compile` and `PlutusTx.compile`?
Hi man Lars answered this in the 7th Q&A video of the Plutus pioneers program cohort 3.
If you don't want to watch the video the long and short of it is that the PlutusTx.TH.compile module is just ...
- 942
1
vote
How do I run doctests?
To run doctest, you don't need to add that to your cabal file. You need to install the doctest executable, and then run cabal repl --with-ghc=doctest. See the doctest documentation.
- 359
1
vote
Canonical example of Smart Contract Verification?
I tried to start a conversation about this here, remains to be seen whether I'll be successful in generating dialogue. But outside of Cardano internals like Ouroboros or the plutus metatheory, the ...
1
vote
Is there any eth_sign equivalent signing method in plutus?
You can find functions for message signing and signature checking in packacke plutus-ledger, module Ledger.Oracle.
Also, why whould you need a smart contract for this?
- 1,816
1
vote
plutus pioneer week01 src code explain
This is part of Template Haskell. It is the way to have Haskell compiled at runtime basically.
This link may help https://downloads.haskell.org/~ghc/7.8.4/docs/html/users_guide/template-haskell.html
$$...
- 211
1
vote
How do I build a debug configuration of a Plutus project?
mkPolicy is an on-chain validator code, is lifted to template Haskell and it gets compiled to core plutus and executed when the UTXO locked by that script is spent. AFAIK, core-plutus is not Haskell, ...
- 171
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