This PR is a continuation of the work done in #276
- Fix PodType in MainPod (we were using `MockMain` instead of `Main`)
- Update anchored keys in statement template arguments to only support wildcards in the origin and literal keys as the key.
- Update the pest grammar accordingly
- Update the parser accordingly
- Rewrite the eth_dos example in a recursive manner so that we use one recursive pod for every distance increment of 1.
- I've also used the podlang to define the eth_dos custom predicates. Currently all predicates are in a single batch (previously `eth_friend` was in a different batch). With #286 we could define `eth_friend` in a different batch again.
- I was feeling a bit creative and used a format macro to pass `Value`s from rust to the podlang code.
- The eth_dos is now written using literals. This resolves https://github.com/0xPARC/pod2/issues/255
- Remove `StatementArg::WildcardValue` in favor of `StatementArg::Literal`. The `WildcardValue` was just a way to have some kind of typing for values that would be used as arguments in custom predicates. Now that we can have literals in any statement this value can be anything, so I just removed the `WildcardValue` and use `Literal` instead. On the backend it was already the case that both cases were treated the same way (after all, `WildcardValue` and `Literal` were 4 fields in the backend).
- Added a new type for Value: `PodId` so that we can use it for custom predicates that take a pod id to be used in a wildcard
- Add a mock vd_set that is empty for tests that don't use plonky2; this allows running those tests individually without paying for the expensive work of calculating the vd for various circuits.
- rename StatementTmplArg::WildcardValue to StatementTmplArg::Wildcard
* migrate from anyhow to thiserror (#190). pending polish error msgs
* Add backtrace and compartmentalize errors
- Include backtraces in the errors we generate. To get this we can't
just return a literal enum, because the backtrace requires a call.
- Related to the previous point: add methods to create errors so
we can include the backtrace conveniently without changing too much
the syntax. So instead of `Err(Error::KeyNotFound(key))` (literal
enum) it will be `Err(Error::key_not_found(key))` (method call)
- Each error should be local to its scope, and each scope should
only return its own error.
- The merkle tree should return `TreeError` and not Error
- The middleware should return `MiddlewareError` and not Error
- With a global Error we can't easily include backend/frontend types in
the error fields, so declare a `BackendError` and a `FrontendError`
and follow the pattern from the previous point
- The Pod traits should be able to return backend errors and will be
used in the frontend; for that we change them to use trait object
Error: `dyn std::error::Error`
* fix error
* apply suggestions from @arnaucube
* rename XError and XResult to Error and Result
* reorg signature
* make frontend custom error more ergonomic
* remove unnecessary feature
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Co-authored-by: Eduard S. <eduardsanou@posteo.net>
