# Validation and Format Utilities

*API Collection*

## Topics

### Validation

- [`GSCaseValidate`](/Core/GlyphsCore/GSCaseValidate) — Whether a value identifies a supported case classification.
- [`GSCaseValidateOrDefault`](/Core/GlyphsCore/GSCaseValidateOrDefault) — A supported case classification, or [`GSCase.GSNoCase`](/Core/GlyphsCore/GSCase/GSNoCase) when the value is not supported.
- [`GSComponentAlignmentValidate`](/Core/GlyphsCore/GSComponentAlignmentValidate)
- [`GSComponentAlignmentValidateOrDefault`](/Core/GlyphsCore/GSComponentAlignmentValidateOrDefault)
- [`GSElementAttachmentValidate`](/Core/GlyphsCore/GSElementAttachmentValidate) — Whether a value is a supported attachment constant.
- [`GSElementAttachmentValidateOrDefault`](/Core/GlyphsCore/GSElementAttachmentValidateOrDefault) — A supported attachment constant, or [`GSElementAttachment.GSElementAttachmentLeft`](/Core/GlyphsCore/GSElementAttachment/GSElementAttachmentLeft) when the value is not supported.
- [`GSElementOrientationValidate`](/Core/GlyphsCore/GSElementOrientationValidate)
- [`GSElementOrientationValidateOrDefault`](/Core/GlyphsCore/GSElementOrientationValidateOrDefault)
- [`GSFigureStylesValidate`](/Core/GlyphsCore/GSFigureStylesValidate) — Whether a value identifies a supported default figure style.
- [`GSFigureStylesValidateOrDefault`](/Core/GlyphsCore/GSFigureStylesValidateOrDefault) — A supported default figure style, or [`GSFigureStyles.GSFigureStylesNotTested`](/Core/GlyphsCore/GSFigureStyles/GSFigureStylesNotTested) when the value is not supported.
- [`GSHandleSizeValidate`](/Core/GlyphsCore/GSHandleSizeValidate) — Whether a value identifies a supported handle size.
- [`GSHandleSizeValidateOrDefault`](/Core/GlyphsCore/GSHandleSizeValidateOrDefault) — A supported handle size, or [`GSHandleSize.GSHandleSizeRegular`](/Core/GlyphsCore/GSHandle/GSHandleSize/GSHandleSizeRegular) when the value is not supported.
- [`GSImageTypeValidate`](/Core/GlyphsCore/GSImageTypeValidate)
- [`GSImageTypeValidateOrDefault`](/Core/GlyphsCore/GSImageTypeValidateOrDefault)
- [`GSLabelColorValidate`](/Core/GlyphsCore/GSLabelColorValidate)
- [`GSLabelColorValidateOrDefault`](/Core/GlyphsCore/GSLabelColorValidateOrDefault)
- [`GSNodeConnectionValidate`](/Core/GlyphsCore/GSNodeConnectionValidate)
- [`GSNodeConnectionValidateOrDefault`](/Core/GlyphsCore/GSNodeConnectionValidateOrDefault)
- [`GSNodeTypeValidate`](/Core/GlyphsCore/GSNodeTypeValidate)
- [`GSNodeTypeValidateOrDefault`](/Core/GlyphsCore/GSNodeTypeValidateOrDefault)
- [`GSOutlineFormatValidate`](/Core/GlyphsCore/GSOutlineFormatValidate) — Whether a value identifies a supported outline format.
- [`GSOutlineFormatValidateOrDefault`](/Core/GlyphsCore/GSOutlineFormatValidateOrDefault) — A supported outline format, or [`GSOutlineFormat.GSOutlineFormatUnknown`](/Core/GlyphsCore/GSOutlineFormat/GSOutlineFormatUnknown) when the value is not supported.
- [`GSPackageTypeValidate`](/Core/GlyphsCore/GSPackageTypeValidate) — Whether a value identifies a supported storage layout.
- [`GSPackageTypeValidateOrDefault`](/Core/GlyphsCore/GSPackageTypeValidateOrDefault) — A supported storage layout, or [`GSPackageType.GSPackageFlatFile`](/Core/GlyphsCore/GSPackageType/GSPackageFlatFile) when the value is not supported.
- [`GSSaveOptionsValidate`](/Core/GlyphsCore/GSSaveOptionsValidate) — Whether a value contains only supported save options.
- [`GSSaveOptionsValidateOrDefault`](/Core/GlyphsCore/GSSaveOptionsValidateOrDefault) — Supported save options, or `GSSaveOptions/default` when the value contains an unsupported option.

### Formats and Grid Settings

- [`GSFileExtensionForOutlineFormat`](/Core/GlyphsCore/GSFileExtensionForOutlineFormat) — The file extension conventionally used for an outline format.
- [`GSNameForOutlineFormat`](/Core/GlyphsCore/GSNameForOutlineFormat) — The font format identifier corresponding to an outline format.
- [`GSIsMeaningfulGrid`](/Core/GlyphsCore/GSIsMeaningfulGrid) — Whether the grid enables coordinate rounding.
- [`GSIsUnitGridOrMore`](/Core/GlyphsCore/GSIsUnitGridOrMore) — Whether either effective grid interval is at least one unit.
- [`GSMakeGridSetting`](/Core/GlyphsCore/GSMakeGridSetting) — Grid settings with the same effective interval in both directions.
- [`GSMultiplicator`](/Core/GlyphsCore/GSMultiplicator)

## See Also

### Utilities

- [String and Value Conversion](/Core/GlyphsCore/String-and-Value-Conversion)
- [Curve Fitting and Offsetting](/Core/GlyphsCore/Curve-Fitting-and-Offsetting)
- [Geometry and Path Operations](/Core/GlyphsCore/Geometry-and-Path-Operations)
- [Miscellaneous Functions](/Core/GlyphsCore/Miscellaneous-Functions)