diff options
| -rw-r--r-- | src/ffi.mjs | 53 |
1 files changed, 30 insertions, 23 deletions
diff --git a/src/ffi.mjs b/src/ffi.mjs index 0fed3b1..73879d6 100644 --- a/src/ffi.mjs +++ b/src/ffi.mjs @@ -104,29 +104,36 @@ export const toProps = (attributes, dispatch) => { return Object.fromEntries( attributes.toArray().map(attr => { - switch (attr.constructor.name) { - case "Attribute": - case "Property": - return [attr.name, attr.value] - - case "Event": - return ['on' + capitalise(attr.name), (e) => attr.handler(e, dispatch)] - - // This should Never Happen™️ but if it does we don't want everything - // to explode, so we'll print a friendly error, ignore the attribute - // and carry on as normal. - default: { - console.warn([ - '[lustre] Oops, I\'m not sure how to handle attributes with ', - 'the type "' + attr.constructor.name + '". Did you try calling ', - 'this function from JavaScript by mistake?', - '', - 'If not, it might be an error in lustre itself. Please open ', - 'an issue at https://github.com/hayleigh-dot-dev/gleam-lustre/issues' - ].join('\n')) - - return [] - } + // The constructors for the `Attribute` type are not public in the + // gleam source to prevent users from constructing them directly. + // This has the unfortunate side effect of not letting us `instanceof` + // the constructors to pattern match on them and instead we have to + // rely on the structure to work out what kind of attribute it is. + // + // This case handles `Attribute` and `Property` variants. + if ('name' in attr && 'value' in attr) { + return [attr.name, attr.value] + } + + // This case handles `Event` variants. + else if ('name' in attr && 'handler' in attr) { + return ['on' + capitalise(attr.name), (e) => attr.handler(e, dispatch)] + } + + // This should Never Happen™️ but if it does we don't want everything + // to explode, so we'll print a friendly error, ignore the attribute + // and carry on as normal. + else { + console.warn([ + '[lustre] Oops, I\'m not sure how to handle attributes with ', + 'the type "' + attr.constructor.name + '". Did you try calling ', + 'this function from JavaScript by mistake?', + '', + 'If not, it might be an error in lustre itself. Please open ', + 'an issue at https://github.com/hayleigh-dot-dev/gleam-lustre/issues' + ].join('\n')) + + return [] } }) ) |