foundation-sequence

Gapless sequential ID generation with human-readable formatting

What it is for

# foundation-sequence

Gapless sequential ID generation with human-readable formatting.

Overview

This crate provides:

• Gapless sequences: Each value is returned exactly once (no gaps from rollbacks)
• Named sequences: Multiple independent sequence counters
• Human-readable formatting: Format patterns like "INV-2024-0001"
• Temporal sequences: Sequences that reset by year, month, or day
• Reset/looping: Sequences that cycle back to initial value

Example

use foundation_sequence::{Sequence, SequenceFormat, TemporalSequence, ResetPeriod};

// Basic sequence
let mut seq = Sequence::new("invoices");
assert_eq!(seq.next(), 1);
assert_eq!(seq.next(), 2);

// With formatting
let fmt = SequenceFormat::new("{prefix}-{value:05}").with_prefix("INV");
assert_eq!(fmt.format(42), "INV-00042");

// Temporal sequence (resets yearly)
let mut yearly = TemporalSequence::new("invoices", ResetPeriod::Yearly)
.with_format("{prefix}-{year}-{value:05}")
.with_prefix("INV");
let result = yearly.next();
// Returns: SequenceValue { value: 1, formatted: "INV-2026-00001", ... }

Capabilities

No public items.

How to use it

From this crate's own rustdoc:

use foundation_sequence::{Sequence, SequenceFormat, TemporalSequence, ResetPeriod};

// Basic sequence
let mut seq = Sequence::new("invoices");
assert_eq!(seq.next(), 1);
assert_eq!(seq.next(), 2);

// With formatting
let fmt = SequenceFormat::new("{prefix}-{value:05}").with_prefix("INV");
assert_eq!(fmt.format(42), "INV-00042");

// Temporal sequence (resets yearly)
let mut yearly = TemporalSequence::new("invoices", ResetPeriod::Yearly)
    .with_format("{prefix}-{year}-{value:05}")
    .with_prefix("INV");
let result = yearly.next();
// Returns: SequenceValue { value: 1, formatted: "INV-2026-00001", ... }

Module structure

No public modules: the crate root is its whole surface.

Public surface

No public items.

Re-exports. Exported here, defined elsewhere.

Boundary

Depends on no other workspace tier.

Shares tier foundation with 27 other crates: foundation-audit-log, foundation-basemodels, foundation-bounded-io, foundation-conversation-closure, foundation-crypto-sign, foundation-decisioning, foundation-encounter-vocabulary, foundation-fs-metadata, … (27 total).

_What this crate deliberately does NOT own is a judgment. No committed registry records one for it, so none is stated here._

Where it sits

Dependencies

Runtime, from outside the workspace.

Development, from outside the workspace.

Build. None.

Depended on by. Nothing in this workspace.

Feature flags

No Cargo features are defined: every capability is unconditional, so no consumer can receive a half-wired crate.

Targets

Error model

No public error type was detected: no public item declares a type named *Error, and no public signature returns one.

Operational characteristics

No unsafe block, unsafe fn, unsafe impl or unsafe trait was found by the parser anywhere in this crate's source.

Configuration

No environment variable is read with a literal name anywhere in this crate. A variable whose key is computed at run time cannot be listed here, and is not claimed to be absent.

Related capabilities

No workspace crate depends on this one.

Verification

What the tests establish, by name:

• test_format_default — src/format.rs
• test_format_serialization — src/format.rs
• test_replace_value_pattern_multiple — src/format.rs
• test_fill_order_numbers_scuba — src/lib.rs
• test_format_complex_pattern — src/lib.rs
• test_format_literal_text — src/lib.rs
• test_format_no_placeholders — src/lib.rs
• test_format_value_only — src/lib.rs
• test_format_value_padded — src/lib.rs
• test_format_with_day — src/lib.rs
• test_format_with_month — src/lib.rs
• test_format_with_prefix — src/lib.rs
• test_format_with_year — src/lib.rs
• test_format_with_year_short — src/lib.rs
• test_invoice_workflow — src/lib.rs
• test_order_number_workflow — src/lib.rs
• test_sequence_error_display — src/lib.rs
• test_sequence_new — src/lib.rs
• test_sequence_next_increments — src/lib.rs
• test_sequence_peek — src/lib.rs
• test_sequence_reset — src/lib.rs
• test_sequence_with_initial — src/lib.rs
• test_sequence_with_reset_loops — src/lib.rs
• test_temporal_daily_reset — src/lib.rs
• test_temporal_daily_sequence_name — src/lib.rs
• test_temporal_monthly_reset — src/lib.rs
• test_temporal_monthly_sequence_name — src/lib.rs
• test_temporal_sequence_next — src/lib.rs
• test_temporal_sequence_next_for_date — src/lib.rs
• test_temporal_yearly_sequence_name — src/lib.rs
• _… 6 more_

Documentation coverage

Metrics

pie showData
    title Rust source composition
    "Code" : 640
    "Blank or comment" : 395

Generation

Rendered by tools-corpus corpus readme from repository evidence alone, renderer schema 2, lexicon current. No model, network service or database was consulted. Regenerate with tools-corpus corpus readme --write; verify with --check.