ErrLookup › sveltejs/svelte
sveltejs/svelte
web development for the rest of us · JavaScript · 442 source files
Analyzed at 20b341f100 on 2026-08-12. 55 documented errors.
| Code / Message | Type | Severity | Tags |
|---|---|---|---|
| 'svelte/compiler' no longer exports a `walk` utility — pleas | exception | error | svelte5, migration, compiler, estree-walker, deprecated |
| migrating this component would require adding a `$${rune}` r | exception | warning | svelte5, migration, runes, naming-collision, codemod |
| Can't migrate code with ${illegal_specifiers.join(' and ')}. | exception | warning | svelte5, migration, imports, codemod, module-script |
| Encountered an export declaration pattern that is not suppor | exception | warning | svelte5, migration, destructuring, props, codemod |
| $$props is used together with named props in a way that cann | exception | warning | svelte5, migration, props, rest-props, codemod |
| can't migrate `${...}` to `$${rune}` because there's a varia | exception | warning | svelte5, migration, runes, naming-collision, codemod |
| can't migrate `: ${...}` to `$${rune}` because there's a var | exception | warning | svelte5, migration, reactive-statements, naming-collision, codemod |
| This migration would change the name of a slot (${slot_name} | exception | warning | svelte5, migration, slots, snippets, naming-collision, codemod |
| This migration would change the name of a slot (${name} to $ | exception | warning | svelte5, migration, slots, snippets, naming-collision, codemod |
| Template must be a string | exception | error | compiler, parser, typeerror, input-validation, node |
async_derived_orphan async_derived_orphan
Cannot create a `$derived(...)` with an `await` expression | exception | error | svelte5, runes, derived, async, runtime, effects |
bind_invalid_checkbox_value bind_invalid_checkbox_value
Using `bind:value` together with a checkbox input is | exception | error | svelte5, runtime, forms, binding, checkbox, input |
bind_invalid_export bind_invalid_export
Component ${component} has an export named `${key}` that a c | exception | error | svelte5, runtime, binding, props, bindable, component-api |
bind_not_bindable bind_not_bindable
A component is attempting to bind to a non-bindable property ` | exception | error | svelte5, runtime, binding, props, bindable |
component_api_changed component_api_changed
Calling `${method}` on a component instance (of ${componen | exception | error | svelte5, runtime, component-api, imperative, migration |
component_api_invalid_new component_api_invalid_new
Attempted to instantiate ${component} with `new ${name | exception | error | svelte5, runtime, component-api, mount, migration |
derived_references_self derived_references_self
A derived value cannot reference itself recursively
http | exception | error | svelte5, runtime, derived, circular, infinite-loop |
each_key_duplicate each_key_duplicate
${value ? `Keyed each block has duplicate key `${value}` at i | exception | error | svelte5, runtime, each, keyed-list, rendering |
each_key_volatile each_key_volatile
Keyed each block has key that is not idempotent — the key for | exception | error | svelte5, runtime, each, keyed-list, idempotency, rendering |
effect_in_teardown effect_in_teardown
`${rune}` cannot be used inside an effect cleanup function
ht | exception | error | svelte5, runtime, effects, runes, lifecycle, cleanup |
effect_in_unowned_derived effect_in_unowned_derived
Effect cannot be created inside a `$derived` value tha | exception | error | svelte, runes, effects, derived, reactivity |
effect_orphan effect_orphan
`${rune}` can only be used inside an effect (e.g. during component | exception | error | svelte, runes, effects, reactivity, lifecycle |
effect_pending_outside_reaction effect_pending_outside_reaction
`$effect.pending()` can only be called inside an | exception | error | svelte, runes, effects, boundary, reactivity |
effect_update_depth_exceeded effect_update_depth_exceeded
Maximum update depth exceeded. This typically indic | exception | critical | svelte, runes, effects, reactivity, infinite-loop, performance |
flush_sync_in_effect flush_sync_in_effect
Cannot use `flushSync` inside an effect
https://svelte.dev/ | exception | error | svelte, runes, effects, flushsync, reactivity |
fork_discarded fork_discarded
Cannot commit a fork that was already discarded
https://svelte.de | exception | error | svelte, fork, experimental, async, state, reactivity |
fork_timing fork_timing
Cannot create a fork inside an effect or when state changes are pend | exception | error | svelte, fork, experimental, async, reactivity, batch |
get_abort_signal_outside_reaction get_abort_signal_outside_reaction
`getAbortSignal()` can only be called inside a | exception | error | svelte, runes, abort-signal, async, effects, derived |
hydratable_missing_but_required hydratable_missing_but_required
Expected to find a hydratable with key `${key}` | exception | error | svelte, hydration, ssr, async, experimental |
hydration_failed hydration_failed
Failed to hydrate the application
https://svelte.dev/e/hydratio | exception | error | svelte, hydration, ssr, rendering |
invalid_snippet invalid_snippet
Could not `{@render}` snippet due to the expression being `null` | exception | error | svelte, snippets, runes, template, rendering |
lifecycle_legacy_only lifecycle_legacy_only
`${name}(...)` cannot be used in runes mode
https://svelte | exception | error | svelte, runes, lifecycle, migration, deprecation |
props_invalid_value props_invalid_value
Cannot do `bind:${key}={undefined}` when `${key}` has a fall | exception | error | svelte, runes, props, binding, two-way-binding |
props_rest_readonly props_rest_readonly
Rest element properties of `$props()` such as `${property}` | exception | error | svelte, runes, props, readonly, dev-only |
rune_outside_svelte rune_outside_svelte
The `${rune}` rune is only available inside `.svelte` and `. | exception | error | svelte, runes, compiler, file-extension, configuration |
set_context_after_init set_context_after_init
`setContext` must be called when a component first initia | exception | error | svelte, context, async, lifecycle, runes |
state_descriptors_fixed state_descriptors_fixed
Property descriptors defined on `$state` objects must co | exception | error | svelte, runes, state, proxy, defineproperty |
state_prototype_fixed state_prototype_fixed
Cannot set prototype of `$state` object
https://svelte.dev | exception | error | svelte, runes, state, proxy, prototype |
state_unsafe_mutation state_unsafe_mutation
Updating state inside `$derived(...)`, `$inspect(...)` or | exception | error | svelte, runes, state, derived, reactivity, mutation |
svelte_boundary_reset_onerror svelte_boundary_reset_onerror
A `<svelte:boundary>` `reset` function cannot be c | exception | error | svelte, error-boundary, runes, rendering |
| value is not async iterable | exception | error | async, iterable, reactivity, runtime, dev-only |
| Your application, or one of its dependencies, imported from | exception | critical | migration, svelte4, svelte5, import, breaking-change, dependencies |
experimental_async_required experimental_async_required
Cannot use `${name}(...)` unless the `experimental.a | exception | error | compiler, async, experimental, config, svelte5 |
invalid_default_snippet invalid_default_snippet
Cannot use `{@render children(...)}` if the parent compo | exception | error | snippets, children, let-directive, slots, svelte5, migration |
invalid_snippet_arguments invalid_snippet_arguments
A snippet function was passed invalid arguments. Snipp | exception | error | snippets, render, svelte5, dev-only |
invariant_violation invariant_violation
An invariant violation occurred, meaning Svelte's internal a | exception | error | internal, bug, invariant, svelte |
lifecycle_outside_component lifecycle_outside_component
`${name}(...)` can only be used during component ini | exception | error | lifecycle, component-init, async, runes, svelte5 |
missing_context missing_context
Context was not set in a parent component
https://svelte.dev/e/m | exception | error | context, getcontext, setcontext, component-tree |
snippet_without_render_tag snippet_without_render_tag
Attempted to render a snippet without a `{@render}` b | exception | error | snippets, render-tag, svelte5, migration, dev-only |
store_invalid_shape store_invalid_shape
`${name}` is not a store with a `subscribe` method
https://s | exception | error | store, subscribe, svelte4, store-contract |
svelte_element_invalid_this_value svelte_element_invalid_this_value
The `this` prop on `<svelte:element>` must be | exception | error | svelte-element, this-prop, dynamic-tag, dom, validation |
| Cannot spring ${typeof current_value} values | exception | error | spring, motion, animation, type, svelte-motion |
| Cannot interpolate values of different type | exception | error | tweened, motion, interpolation, type, svelte-motion |
| Object cannot be null | exception | error | tweened, motion, null, interpolation, svelte-motion |
| derived() expects stores as input, got a falsy value | exception | error | store, derived, validation, svelte-store |