Validation Results for ExampleIG

Generated Fri Oct 18 08:18:01 UTC 2024, FHIR version 4.0.1 for my-ig#1.0.0 (canonical = http://example.com/fhir/example (history)). See Full QA Report

Quality Checks
Publisher Version:IG Publisher Version: v1.6.31
Publication Code:n/a . PackageId = my-ig, Canonical = http://example.com/fhir/example
Realm Check for n/a:
  • n/a
Publication Request:
  • History Page 'history.html' is wrong (ig.json#paths/history) - must be 'http://example.com/fhir/example/history.html'
  • This IG has never been published
  • This IG has never been published, so the version should start with '0.' or include a patch version e.g. '-ballot'
  • No publication request found
Supressed Messages:5 Suppressed Issues
Dependency Checks:
PackageVersionFHIRCanonicalWeb BaseComment
.. my-ig1.0.0R4http://example.com/fhir/example
... hl7.terminology.r46.0.2 MR4http://terminology.hl7.orghttp://terminology.hl7.org/6.0.2
... hl7.fhir.uv.extensions.r45.1.0 MR4http://hl7.org/fhir/extensionshttp://hl7.org/fhir/extensions/5.1.0
Templates: hl7.fhir.affiliate.custom.template#0.0.1 -> hl7.fhir.affiliate.template#current -> fhir.base.template#current. Tools: 0.2.0
Dependent IGs:no references
Global Profiles:(none declared)
Terminology Server(s):http://tx.fhir.org/r4 (details)
HTA Analysis:Non-HL7 Igs are exempt from terminology dependency analysis
R5 Dependencies:(none)
Draft Dependencies:
Modifier Extensions:(none)
Previous Version Comparison: Unable to compare with previous version: Unable to find version history at http://example.com/fhir/example (Problem #1 with package-list.json at http://example.com/fhir/example: Not Found)
IPA Comparison: n/a
IPS Comparison: n/a
Validation Flags: On: autoLoad; Off: hintAboutNonMustSupport, anyExtensionsAllowed, checkAggregation, showReferenceMessages, noExperimentalContent, displayWarnings
Summary: errors = 39, warn = 29, info = 0, broken links = 12
FilenameErrorsWarningsHints
Build Errors1280
/scratch/repo/fsh-generated/resources/ImplementationGuide-my-ig300
/scratch/repo/fsh-generated/resources/StructureDefinition-PRreferral-ABE010
/scratch/repo/fsh-generated/resources/StructureDefinition-PRreferral-CAT010
/scratch/repo/fsh-generated/resources/StructureDefinition-PRreferral-FEV1010
/scratch/repo/fsh-generated/resources/StructureDefinition-PRreferral-SpO2010
/scratch/repo/fsh-generated/resources/StructureDefinition-PRreferral-comorbidities010
/scratch/repo/fsh-generated/resources/StructureDefinition-PRreferral-exacerbation010
/scratch/repo/fsh-generated/resources/StructureDefinition-PRreferral-mMRC010
/scratch/repo/fsh-generated/resources/ValueSet-PRreferral-valueset-ICD10310
/scratch/repo/fsh-generated/resources/ValueSet-PRreferral-valueset-LOINC010
/scratch/repo/fsh-generated/resources/ValueSet-PRreferral-valueset-SNOMED010
/scratch/repo/input/examples/PRreferral-ABE-example920
/scratch/repo/input/examples/PRreferral-CAT-example320
/scratch/repo/input/examples/PRreferral-FEV1-example310
/scratch/repo/input/examples/PRreferral-SpO2-example920
/scratch/repo/input/examples/PRreferral-comorbidities300
/scratch/repo/input/examples/PRreferral-exacerbation-example320
/scratch/repo/input/examples/PRreferral-mMRC-example320

n/a Show Validation Information

ImplementationGuide.urlwarningThe canonical URL for an Implementation Guide must point directly to the implementation guide resource, not to the Implementation Guide as a whole
warningUnable to find ImplementationGuide.definition.resource.description for the resource Observation/ABC_example. Descriptions are strongly encouraged if they cannot be inferred from the resource to allow proper population of the artifact list.
warningUnable to find ImplementationGuide.definition.resource.description for the resource Observation/CAT_score_example. Descriptions are strongly encouraged if they cannot be inferred from the resource to allow proper population of the artifact list.
warningUnable to find ImplementationGuide.definition.resource.description for the resource Observation/FEV1_example. Descriptions are strongly encouraged if they cannot be inferred from the resource to allow proper population of the artifact list.
warningUnable to find ImplementationGuide.definition.resource.description for the resource Observation/SpO2_example. Descriptions are strongly encouraged if they cannot be inferred from the resource to allow proper population of the artifact list.
warningUnable to find ImplementationGuide.definition.resource.description for the resource Condition/comorbidities_example. Descriptions are strongly encouraged if they cannot be inferred from the resource to allow proper population of the artifact list.
warningUnable to find ImplementationGuide.definition.resource.description for the resource Observation/exacerbation_history_example. Descriptions are strongly encouraged if they cannot be inferred from the resource to allow proper population of the artifact list.
warningUnable to find ImplementationGuide.definition.resource.description for the resource Observation/mMRC_score_example. Descriptions are strongly encouraged if they cannot be inferred from the resource to allow proper population of the artifact list.
output​/Condition-comorbidities_example​.html​#​/html​/body​/div​/div​/div​/div​/div​/div​/p​/a at Line 189, column 705errorThe link 'cfsb1724237080279' for "cfsb1724237080279" cannot be resolved
output​/Observation-ABC_example​.html​#​/html​/body​/div​/div​/div​/div​/div​/div​/p​/a at Line 189, column 278errorThe link 'cfsb1724237080279' for "cfsb1724237080279" cannot be resolved
output​/Observation-ABC_example​.html​#​/html​/body​/div​/div​/div​/div​/div​/div​/ul​/li​/a at Line 189, column 388errorThe link 'cfsb1722869801967' for "cfsb1722869801967" cannot be resolved
output​/Observation-ABC_example​.html​#​/html​/body​/div​/div​/div​/div​/div​/div​/ul​/li​/a at Line 189, column 446errorThe link 'cfsb1722867963666' for "cfsb1722867963666" cannot be resolved
output​/Observation-ABC_example​.html​#​/html​/body​/div​/div​/div​/div​/div​/div​/ul​/li​/a at Line 189, column 504errorThe link 'cfsb1722869550199' for "cfsb1722869550199" cannot be resolved
output​/Observation-CAT_score_example​.html​#​/html​/body​/div​/div​/div​/div​/div​/div​/p​/a at Line 189, column 297errorThe link 'cfsb1724237080279' for "cfsb1724237080279" cannot be resolved
output​/Observation-FEV1_example​.html​#​/html​/body​/div​/div​/div​/div​/div​/div​/p​/a at Line 189, column 381errorThe link 'cfsb1724237080279' for "cfsb1724237080279" cannot be resolved
output​/Observation-SpO2_example​.html​#​/html​/body​/div​/div​/div​/div​/div​/div​/p​/a at Line 189, column 353errorThe link 'cfsb1724237080279' for "cfsb1724237080279" cannot be resolved
output​/Observation-exacerbation_history_example​.html​#​/html​/body​/div​/div​/div​/div​/div​/div​/p​/a at Line 189, column 466errorThe link 'cfsb1724237080279' for "cfsb1724237080279" cannot be resolved
output​/Observation-mMRC_score_example​.html​#​/html​/body​/div​/div​/div​/div​/div​/div​/p​/a at Line 189, column 398errorThe link 'cfsb1724237080279' for "cfsb1724237080279" cannot be resolved
output​/background​.html​#​/html​/body​/div​/div​/div​/div​/div​/p​/img at Line 250, column 5errorThe image source '/Users/nadiahipolito/Downloads/fhir-master/input/images/Image1.jpg' cannot be resolved
output​/background​.html​#​/html​/body​/div​/div​/div​/div​/div​/p​/img at Line 263, column 5errorThe image source '/Users/nadiahipolito/Downloads/fhir-master/input/images/Image2.png' cannot be resolved

fsh-generated/resources/ImplementationGuide-my-ig.json Show Validation Information (1)

PathSeverityMessage
ImplementationGuide​.where(url = 'http:​/​/example​.com​/fhir​/example')errorConformance resource /scratch/repo/fsh-generated/resources/ImplementationGuide-my-ig.json - the canonical URL (http://example.com/fhir/example/ImplementationGuide/my-ig) does not match the URL (http://example.com/fhir/example)
ImplementationGuide.urlerrorResource id/url mismatch: my-ig/http://example.com/fhir/example
fsh-generated​/resources​/ImplementationGuide-my-igerrorURL Mismatch http://example.com/fhir/example/ImplementationGuide/my-ig vs http://example.com/fhir/example

fsh-generated/resources/StructureDefinition-PRreferral-ABE.json Show Validation Information (1)

PathSeverityMessage
StructureDefinition​.where(url = 'http:​/​/example​.com​/fhir​/example​/StructureDefinition​/PRreferral-ABE')warningThe Implementation Guide contains no examples for this profile

fsh-generated/resources/StructureDefinition-PRreferral-CAT.json Show Validation Information (1)

PathSeverityMessage
StructureDefinition​.where(url = 'http:​/​/example​.com​/fhir​/example​/StructureDefinition​/PRreferral-CAT')warningThe Implementation Guide contains no examples for this profile

fsh-generated/resources/StructureDefinition-PRreferral-FEV1.json Show Validation Information (1)

PathSeverityMessage
StructureDefinition​.where(url = 'http:​/​/example​.com​/fhir​/example​/StructureDefinition​/PRreferral-FEV1')warningThe Implementation Guide contains no examples for this profile

fsh-generated/resources/StructureDefinition-PRreferral-SpO2.json Show Validation Information (1)

PathSeverityMessage
StructureDefinition​.where(url = 'http:​/​/example​.com​/fhir​/example​/StructureDefinition​/PRreferral-SpO2')warningThe Implementation Guide contains no examples for this profile

fsh-generated/resources/StructureDefinition-PRreferral-comorbidities.json Show Validation Information (1)

PathSeverityMessage
StructureDefinition​.where(url = 'http:​/​/example​.com​/fhir​/example​/StructureDefinition​/PRreferral-comorbidities')warningThe Implementation Guide contains no examples for this profile

fsh-generated/resources/StructureDefinition-PRreferral-exacerbation.json Show Validation Information (1)

PathSeverityMessage
StructureDefinition​.where(url = 'http:​/​/example​.com​/fhir​/example​/StructureDefinition​/PRreferral-exacerbation')warningThe Implementation Guide contains no examples for this profile

fsh-generated/resources/StructureDefinition-PRreferral-mMRC.json Show Validation Information (1)

PathSeverityMessage
StructureDefinition​.where(url = 'http:​/​/example​.com​/fhir​/example​/StructureDefinition​/PRreferral-mMRC')warningThe Implementation Guide contains no examples for this profile

fsh-generated/resources/ValueSet-PRreferral-valueset-ICD10.json Show Validation Information (1)

PathSeverityMessage
ValueSet.compose.include[0].filter[0]errorThe value for a filter based on property 'concept' must be a valid code from the system 'http://hl7.org/fhir/sid/icd-10', and '4A09XLZ' is not (Unknown code '4A09XLZ' in the CodeSystem 'http://hl7.org/fhir/sid/icd-10' version '2019-covid-expanded')
ValueSet.compose.include[1].filter[0]errorThe value for a filter based on property 'concept' must be a valid code from the system 'http://hl7.org/fhir/sid/icd-10', and '4A03XR1' is not (Unknown code '4A03XR1' in the CodeSystem 'http://hl7.org/fhir/sid/icd-10' version '2019-covid-expanded')
ValueSet (l1/c1753)warningPublished value sets SHOULD conform to the ShareableValueSet profile, which says that the element ValueSet.experimental is mandatory, but it is not present
ValueSet​.where(id = 'PRreferral-valueset-ICD10')errorError from http://tx.fhir.org/r4: Unable to locate code 4A09XLZ (from server, see log)

fsh-generated/resources/ValueSet-PRreferral-valueset-LOINC.json Show Validation Information (1)

PathSeverityMessage
ValueSet (l1/c1701)warningPublished value sets SHOULD conform to the ShareableValueSet profile, which says that the element ValueSet.experimental is mandatory, but it is not present

fsh-generated/resources/ValueSet-PRreferral-valueset-SNOMED.json Show Validation Information (1)

PathSeverityMessage
ValueSet (l1/c2368)warningPublished value sets SHOULD conform to the ShareableValueSet profile, which says that the element ValueSet.experimental is mandatory, but it is not present

input/examples/PRreferral-ABE-example.json Show Validation Information (1)

PathSeverityMessage
Observation.id (l5/c22)errorInvalid Resource id: Invalid Characters ('ABC_example')
Observation.subject (l11/c4)errorUnable to resolve resource with reference 'cfsb1724237080279'
Observation.derivedFrom[0] (l15/c6)errorUnable to resolve resource with reference 'cfsb1722869801967'
Observation.derivedFrom[1] (l18/c6)errorUnable to resolve resource with reference 'cfsb1722867963666'
Observation.derivedFrom[2] (l21/c6)errorUnable to resolve resource with reference 'cfsb1722869550199'
Observation (l3/c2)warningBest Practice Recommendation: In general, all observations should have a performer
Observation (l3/c2)warningBest Practice Recommendation: In general, all observations should have an effective[x] ()
Observation.text.diverrorHyperlink 'cfsb1724237080279' at 'div/p/a' for 'cfsb1724237080279' does not resolve
Observation.text.diverrorHyperlink 'cfsb1722869801967' at 'div/ul/li/a' for 'cfsb1722869801967' does not resolve
Observation.text.diverrorHyperlink 'cfsb1722867963666' at 'div/ul/li/a' for 'cfsb1722867963666' does not resolve
Observation.text.diverrorHyperlink 'cfsb1722869550199' at 'div/ul/li/a' for 'cfsb1722869550199' does not resolve

input/examples/PRreferral-CAT-example.json Show Validation Information (1)

PathSeverityMessage
Observation.id (l3/c30)errorInvalid Resource id: Invalid Characters ('CAT_score_example')
Observation.subject (l9/c6)errorUnable to resolve resource with reference 'cfsb1724237080279'
Observation (l1/c4)warningBest Practice Recommendation: In general, all observations should have a performer
Observation (l1/c4)warningBest Practice Recommendation: In general, all observations should have an effective[x] ()
Observation.text.diverrorHyperlink 'cfsb1724237080279' at 'div/p/a' for 'cfsb1724237080279' does not resolve

input/examples/PRreferral-FEV1-example.json Show Validation Information (1)

PathSeverityMessage
Observation.id (l3/c23)errorInvalid Resource id: Invalid Characters ('FEV1_example')
Observation.subject (l19/c4)errorUnable to resolve resource with reference 'cfsb1724237080279'
Observation (l1/c2)warningBest Practice Recommendation: In general, all observations should have a performer
Observation.text.diverrorHyperlink 'cfsb1724237080279' at 'div/p/a' for 'cfsb1724237080279' does not resolve

input/examples/PRreferral-SpO2-example.json Show Validation Information (1)

PathSeverityMessage
Observation.id (l3/c25)errorInvalid Resource id: Invalid Characters ('SpO2_example')
Observation.subject (l8/c6)errorUnable to resolve resource with reference 'cfsb1724237080279'
Observation (l1/c4)errorObservation.category: minimum required = 1, but only found 0 (from http://hl7.org/fhir/StructureDefinition/oxygensat|4.0.1)
Observation (l1/c4)errorSlice 'Observation.category:VSCat': a matching slice is required, but not found (from http://hl7.org/fhir/StructureDefinition/oxygensat|4.0.1). Note that other slices are allowed in addition to this required slice
Observation (l1/c4)errorObservation.effective[x]: minimum required = 1, but only found 0 (from http://hl7.org/fhir/StructureDefinition/oxygensat|4.0.1)
Observation.code (l11/c6)errorOxygenSatCode: magic LOINC code 2708-6 required, but not found (from http://hl7.org/fhir/StructureDefinition/oxygensat|4.0.1). Note that other Observation codes are allowed in addition to this required magic code
Observation​.value​.ofType(Quantity) (l4​/c6)errorObservation.value[x]:valueQuantity.system: minimum required = 1, but only found 0 (from http://hl7.org/fhir/StructureDefinition/oxygensat|4.0.1)
Observation​.value​.ofType(Quantity) (l4​/c6)errorObservation.value[x]:valueQuantity.code: minimum required = 1, but only found 0 (from http://hl7.org/fhir/StructureDefinition/oxygensat|4.0.1)
Observation (l1/c4)warningBest Practice Recommendation: In general, all observations should have a performer
Observation (l1/c4)warningBest Practice Recommendation: In general, all observations should have an effective[x] ()
Observation.text.diverrorHyperlink 'cfsb1724237080279' at 'div/p/a' for 'cfsb1724237080279' does not resolve

input/examples/PRreferral-comorbidities.json Show Validation Information (1)

PathSeverityMessage
Condition.id (l3/c34)errorInvalid Resource id: Invalid Characters ('comorbidities_example')
Condition.subject (l40/c6)errorUnable to resolve resource with reference 'cfsb1724237080279'
Condition.text.diverrorHyperlink 'cfsb1724237080279' at 'div/p/a' for 'cfsb1724237080279' does not resolve

input/examples/PRreferral-exacerbation-example.json Show Validation Information (1)

PathSeverityMessage
Observation.id (l3/c41)errorInvalid Resource id: Invalid Characters ('exacerbation_history_example')
Observation.subject (l15/c6)errorUnable to resolve resource with reference 'cfsb1724237080279'
Observation (l1/c4)warningBest Practice Recommendation: In general, all observations should have a performer
Observation (l1/c4)warningBest Practice Recommendation: In general, all observations should have an effective[x] ()
Observation.text.diverrorHyperlink 'cfsb1724237080279' at 'div/p/a' for 'cfsb1724237080279' does not resolve

input/examples/PRreferral-mMRC-example.json Show Validation Information (1)

PathSeverityMessage
Observation.id (l3/c31)errorInvalid Resource id: Invalid Characters ('mMRC_score_example')
Observation.subject (l5/c6)errorUnable to resolve resource with reference 'cfsb1724237080279'
Observation (l1/c4)warningBest Practice Recommendation: In general, all observations should have a performer
Observation (l1/c4)warningBest Practice Recommendation: In general, all observations should have an effective[x] ()
Observation.text.diverrorHyperlink 'cfsb1724237080279' at 'div/p/a' for 'cfsb1724237080279' does not resolve

Suppressed Messages (Warnings, hints, broken links)

If this was a real IG, there should be examples for these profiles too. But it's not, and I'm lazy...

This is inherited from the base resource

We're expecting these to not match the slice - we're showing how you can use slicing to define the one repetition you want even when many repetitions might be present

Errors sorted by type


All_observations_should_have_a_performer

input/examples/PRreferral-ABE-example.jsonBest Practice Recommendation: In general, all observations should have a performer
input/examples/PRreferral-CAT-example.jsonBest Practice Recommendation: In general, all observations should have a performer
input/examples/PRreferral-FEV1-example.jsonBest Practice Recommendation: In general, all observations should have a performer
input/examples/PRreferral-SpO2-example.jsonBest Practice Recommendation: In general, all observations should have a performer
input/examples/PRreferral-exacerbation-example.jsonBest Practice Recommendation: In general, all observations should have a performer
input/examples/PRreferral-mMRC-example.jsonBest Practice Recommendation: In general, all observations should have a performer

All_observations_should_have_an_effectiveDateTime_or_an_effectivePeriod

input/examples/PRreferral-ABE-example.jsonBest Practice Recommendation: In general, all observations should have an effective[x] ()
input/examples/PRreferral-CAT-example.jsonBest Practice Recommendation: In general, all observations should have an effective[x] ()
input/examples/PRreferral-SpO2-example.jsonBest Practice Recommendation: In general, all observations should have an effective[x] ()
input/examples/PRreferral-exacerbation-example.jsonBest Practice Recommendation: In general, all observations should have an effective[x] ()
input/examples/PRreferral-mMRC-example.jsonBest Practice Recommendation: In general, all observations should have an effective[x] ()

RESOURCE_CANONICAL_MISMATCH

fsh-generated/resources/ImplementationGuide-my-ig.jsonConformance resource /scratch/repo/fsh-generated/resources/ImplementationGuide-my-ig.json - the canonical URL (http://example.com/fhir/example/ImplementationGuide/my-ig) does not match the URL (http://example.com/fhir/example)

RESOURCE_ID_MISMATCH

fsh-generated/resources/ImplementationGuide-my-ig.jsonResource id/url mismatch: my-ig/http://example.com/fhir/example

Reference_REF_CantResolve

input/examples/PRreferral-ABE-example.jsonUnable to resolve resource with reference 'cfsb1724237080279'
input/examples/PRreferral-ABE-example.jsonUnable to resolve resource with reference 'cfsb1722869801967'
input/examples/PRreferral-ABE-example.jsonUnable to resolve resource with reference 'cfsb1722867963666'
input/examples/PRreferral-ABE-example.jsonUnable to resolve resource with reference 'cfsb1722869550199'
input/examples/PRreferral-CAT-example.jsonUnable to resolve resource with reference 'cfsb1724237080279'
input/examples/PRreferral-FEV1-example.jsonUnable to resolve resource with reference 'cfsb1724237080279'
input/examples/PRreferral-SpO2-example.jsonUnable to resolve resource with reference 'cfsb1724237080279'
input/examples/PRreferral-comorbidities.jsonUnable to resolve resource with reference 'cfsb1724237080279'
input/examples/PRreferral-exacerbation-example.jsonUnable to resolve resource with reference 'cfsb1724237080279'
input/examples/PRreferral-mMRC-example.jsonUnable to resolve resource with reference 'cfsb1724237080279'

Resource_RES_ID_Malformed_Chars

input/examples/PRreferral-ABE-example.jsonInvalid Resource id: Invalid Characters ('ABC_example')
input/examples/PRreferral-CAT-example.jsonInvalid Resource id: Invalid Characters ('CAT_score_example')
input/examples/PRreferral-FEV1-example.jsonInvalid Resource id: Invalid Characters ('FEV1_example')
input/examples/PRreferral-SpO2-example.jsonInvalid Resource id: Invalid Characters ('SpO2_example')
input/examples/PRreferral-comorbidities.jsonInvalid Resource id: Invalid Characters ('comorbidities_example')
input/examples/PRreferral-exacerbation-example.jsonInvalid Resource id: Invalid Characters ('exacerbation_history_example')
input/examples/PRreferral-mMRC-example.jsonInvalid Resource id: Invalid Characters ('mMRC_score_example')

VALIDATION_VAL_PROFILE_MINIMUM_MAGIC

input/examples/PRreferral-SpO2-example.jsonOxygenSatCode: magic LOINC code 2708-6 required, but not found (from http://hl7.org/fhir/StructureDefinition/oxygensat|4.0.1). Note that other Observation codes are allowed in addition to this required magic code

VALUESET_BAD_FILTER_VALUE_VALID_CODE

fsh-generated/resources/ValueSet-PRreferral-valueset-ICD10.jsonThe value for a filter based on property 'concept' must be a valid code from the system 'http://hl7.org/fhir/sid/icd-10', and '4A09XLZ' is not (Unknown code '4A09XLZ' in the CodeSystem 'http://hl7.org/fhir/sid/icd-10' version '2019-covid-expanded')
fsh-generated/resources/ValueSet-PRreferral-valueset-ICD10.jsonThe value for a filter based on property 'concept' must be a valid code from the system 'http://hl7.org/fhir/sid/icd-10', and '4A03XR1' is not (Unknown code '4A03XR1' in the CodeSystem 'http://hl7.org/fhir/sid/icd-10' version '2019-covid-expanded')

Validation_VAL_Profile_Minimum

input/examples/PRreferral-SpO2-example.jsonObservation.category: minimum required = 1, but only found 0 (from http://hl7.org/fhir/StructureDefinition/oxygensat|4.0.1)
input/examples/PRreferral-SpO2-example.jsonObservation.effective[x]: minimum required = 1, but only found 0 (from http://hl7.org/fhir/StructureDefinition/oxygensat|4.0.1)
input/examples/PRreferral-SpO2-example.jsonObservation.value[x]:valueQuantity.system: minimum required = 1, but only found 0 (from http://hl7.org/fhir/StructureDefinition/oxygensat|4.0.1)
input/examples/PRreferral-SpO2-example.jsonObservation.value[x]:valueQuantity.code: minimum required = 1, but only found 0 (from http://hl7.org/fhir/StructureDefinition/oxygensat|4.0.1)

Validation_VAL_Profile_Minimum_SLICE

input/examples/PRreferral-SpO2-example.jsonSlice 'Observation.category:VSCat': a matching slice is required, but not found (from http://hl7.org/fhir/StructureDefinition/oxygensat|4.0.1). Note that other slices are allowed in addition to this required slice