Enumerations

Velox PascalScript enumerations are named ordinal types. Unless stated otherwise, the first declared member has ordinal 0 and each following member increases by one. The name is the stable scripting concept; the numeric ordinal is an implementation detail that can drift when an importer omits, inserts or reorders a host value.

Select an enumeration

Area	Enumeration	Use	Critical boundary
Client datasets	TDataPacketFormat	Binary or XML packet serialization	Format controls bytes and encoding, not logical rows.
Lists	TDuplicates	Sorted-list duplicate policy	Comparison rules and existing entries affect results.
Datasets	TFieldType	Field/parameter logical type	Script importer omits host ftLargeUint.
HTTP	TIdHTTPProtocolVersion	HTTP/1.0 or 1.1	This is separate from TLS.
Mail	TIdMessageEncoding	Whole-message layout	Not character or transfer encoding.
Mail	TIdMessageFlags	IMAP message state	Flags normally travel in a set.
Mail	TIdMessagePartType	Text versus attachment part	Result follows runtime class behavior.
Mail	TIdMessagePriority	Five-level message priority	Ordinals map to X-Priority 1..5.
PascalScript VM	TIFException	Runtime error category	Parameter meaning depends on the error member.
JSON	TJSONValueType	Runtime JSON value kind	Guard conversions by kind and null state.
Datasets	TLocateOption	Locate matching behavior	Used through TLocateOptions; provider behavior matters.
XML	TsdElementType	NativeXML node kind	Raw navigation includes non-element nodes.
Authentication	TvxAuthType	Basic, bearer, OAuth or Windows selection	Script importer omits host fatNTLM.
File audit	TvxFileEventType	File lifecycle event	Omitted host fetDownload shifts later ordinals.
File definitions	TvxFileType	Legacy file parser family	fftExcel is an old alias-like member.
OAuth	TvxGrantType	Grant flow	Password grant is obsolete; Auto is provider data.
HTTP	TvxHTTPMethod	Request method or routing sentinel	Any/Custom are not ordinary fixed methods.
Logging	TvxLogStatusType	Outcome/severity state	Status drives persistence, routing and notifications.
TLS	TvxSSLClientType	SSL/TLS protocol mapping	Several labels collapse to TLS 1.2.
TLS	TvxTLSType	No, implicit or explicit TLS policy	Require and explicit modes have different failure behavior.

Rules for technical consumers

• Compare named members and use case statements. Do not persist Ord(...) unless the same exact importer declaration is part of the data contract.
• An enumeration is one value. A set of type can hold zero or more members; see the separate Sets branch.
• Validate values entering through configuration, JSON, databases, Variants or numeric casts before assigning them to an enumeration.
• Treat importer/host mismatches as type-boundary defects. TvxFileEventType has a shifted ordinal after omitted fetDownload; TvxAuthType omits trailing fatNTLM; TFieldType omits trailing ftLargeUint.
• Low, High, Ord, Pred and Succ express ordinal mechanics but do not provide business meaning. Prefer explicit named mapping tables.
• Code Library declarations for TFieldType and TIFException were truncated to 300 characters in the generated index; their child pages reconstruct the complete script registration from product source.

External references

• Embarcadero enumerated types - Delphi ordinal ordering and operations.
• Free Pascal ordinal types - compatible enumeration language model.

Created 2026-07-15