Built-in Types & Formats

This page is the definitive reference for every type Repl can bind from a route segment or command-line token, and every input format each type accepts.

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Scalar types

These types are usable as route constraints ({name:type}) and are inferred automatically from handler parameter types.

Constraint name(s)	.NET type	Accepted input
string (default)	string	Any single token
alpha	string	Letters only ([a-zA-Z]+)
int	int	Integer — e.g. 42, -7, 1_000
long	long	Large integer — e.g. 1000000000
bool	bool	true or false
double	double	Floating point — e.g. 3.14, -0.5
guid	Guid	Standard GUID — e.g. 123e4567-e89b-12d3-a456-426614174000
email	string	Valid email address — e.g. user@example.com
uri	Uri	Any URI — e.g. https://example.com
url	Uri	HTTP/HTTPS URL with valid host
urn	Uri	URN — e.g. urn:isbn:0451450523

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Temporal scalar types

Temporal scalars capture a single point in time or a duration. Each has one or more constraint name aliases — any alias is interchangeable.

date / dateonly / date-only

Binds to DateOnly.

Format	Example
yyyy-MM-dd	2024-01-15

datetime / date-time

Binds to DateTime.

Format	Example
yyyy-MM-dd	2024-01-15
yyyy-MM-ddTHH:mm	2024-01-15T10:30
yyyy-MM-dd HH:mm	2024-01-15 10:30
yyyy-MM-ddTHH:mm:ss	2024-01-15T10:30:45

datetimeoffset / date-time-offset

Binds to DateTimeOffset. Accepts all datetime formats plus an optional timezone designator appended to the datetime.

Format	Example
yyyy-MM-dd	2024-01-15
yyyy-MM-ddTHH:mm	2024-01-15T10:30
yyyy-MM-ddTHH:mmK	2024-01-15T10:30+05:00
yyyy-MM-ddTHH:mm:ss	2024-01-15T10:30:45
yyyy-MM-ddTHH:mm:ssK	2024-01-15T10:30:45Z
ISO 8601 round-trip	2024-01-15T10:30:45.0000000+05:00

K is any valid offset: Z (UTC), +HH:mm, or -HH:mm.

time / timeonly / time-only

Binds to TimeOnly.

Format	Example
HH:mm	14:30
HH:mm:ss	14:30:45

timespan / time-span

Binds to TimeSpan. Three format families are accepted; mixing families within a single value is not supported.

Compact duration

Compact tokens for each unit:

Suffix	Unit	Example
d	Days	30d
h	Hours	8h
m	Minutes	30m
s	Seconds	45s
ms	Milliseconds	500ms

Combine units in descending order (d → h → m → s → ms). Underscore separators are optional:

1h30m          → 1 hour 30 minutes
2d4h           → 2 days 4 hours
1h30m45s       → 1 hour 30 minutes 45 seconds
1h_30m_45s     → same, with separators

ISO 8601 duration

P30D           → 30 days
PT8H           → 8 hours
P1DT2H30M      → 1 day, 2 hours, 30 minutes
PT1H30M45S     → 1 hour, 30 minutes, 45 seconds

Standard .NET colon format

HH:mm:ss       → e.g.  08:30:00
d.HH:mm:ss     → e.g.  1.08:30:00  (1 day, 8 hours, 30 minutes)

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Temporal range types

Temporal ranges capture an interval — a start and an end — from a single token. There are three types, one per temporal precision:

.NET type	Start/end type	Duration constraint
ReplDateRange	DateOnly	Duration must be whole days (d only, no sub-day units)
ReplDateTimeRange	DateTime	Any TimeSpan format
ReplDateTimeOffsetRange	DateTimeOffset	Any TimeSpan format

All three types expose .From and .To properties of their respective type.

Note

Temporal range types are used as handler parameter types, not as constraint names. Repl infers the binding automatically when the parameter type is ReplDateRange, ReplDateTimeRange, or ReplDateTimeOffsetRange.

Syntax

Two forms are accepted for all three range types:

start..end        # inclusive start-to-end range
start@duration    # start plus a forward duration

Timestamp formats

The timestamp format depends on the range type:

ReplDateRange — uses date format:

2024-01-15

ReplDateTimeRange — uses datetime formats:

2024-01-15
2024-01-15T10:30
2024-01-15 10:30
2024-01-15T10:30:45

ReplDateTimeOffsetRange — uses datetimeoffset formats:

2024-01-15
2024-01-15T10:30
2024-01-15T10:30+05:00
2024-01-15T10:30:45Z

Duration formats (for @duration)

The duration part accepts all TimeSpan formats listed above, subject to the type constraint:

• ReplDateRange@duration — whole-day units only: @30d, @P30D are valid; sub-day or calendar units (@8h, @P1M, @PT30M) are not valid
• ReplDateTimeRange@duration — any TimeSpan format, e.g. @8h30m
• ReplDateTimeOffsetRange@duration — any TimeSpan format

Examples

# Date-only range
myapp report --period 2024-01-01..2024-03-31
myapp report --period 2024-01-01@90d

# DateTime range — narrow to hours
myapp logs --range 2024-03-15T08:00..2024-03-15T18:00
myapp logs --range 2024-03-15T08:00@8h

# DateTimeOffset range — cross-timezone audit window
myapp audit --window 2024-01-15T00:00:00Z..2024-01-15T23:59:59Z
myapp audit --window 2024-01-15T00:00:00Z@1d

Route registration

// Inferred from parameter type — no constraint name needed
app.Map("report period", (ReplDateRange period) => commands.Report(period));
app.Map("logs range", (ReplDateTimeRange range) => commands.Logs(range));
app.Map("audit window", (ReplDateTimeOffsetRange window) => commands.Audit(window));

// CLI usage
// myapp report period --period 2024-01-01..2024-03-31
// myapp logs range --range 2024-03-15T08:00@8h
// myapp audit window --window 2024-01-15T00:00:00Z@1d