core.wait: a leaf whose whole meaning is its config (ADR-0002 decision
10).
No slots, one :duration field. The duration is a string rather than a
number of seconds because ADR-0001 decision 6 forbids floats in
config, and a bare integer would have to carry its unit somewhere
else.
Either stored spelling is accepted: a predicator duration string
("1h30m", "2d", "3d8h"), which is the primary form and the one the
author types, or ISO-8601 with integer components ("PT30S", "PT48H",
"P1D"). Whichever was typed is what config holds, verbatim;
StatifierBlocks.Core.Duration is where the two meet and the ISO pivot
is taken at emit time. That is ADR-0005's 2026-08-29 :duration
amendment, under which this type "comes to accept both spellings the way
core.send already does" - and it is the whole of why a "48h" this
type once refused is now a duration.
This type validates the string; it does not resolve it to a number of milliseconds, mint a timer, or know that durable timers exist. Turning it into a delayed send is the compiler's job.
Summary
Functions
A compound state that sends itself a delayed event on entry and finishes when that event arrives.
A wait constrains nothing and is constrained by nothing beyond being a
step: it declares kinds and leaves consumes and produces to
ADR-0003 decision 5's permissive default, since waiting transforms no
data.
Functions
A compound state that sends itself a delayed event on entry and finishes when that event arrives.
<state id="s_WAI" initial="s_WAI__waiting">
<state id="s_WAI__waiting">
<onentry><send delay="48h" event="statifier_blocks.wait.blk_WAI" id="s_WAI__send"/></onentry>
<transition event="statifier_blocks.wait.blk_WAI" target="s_WAI__done"/>
</state>
<final id="s_WAI__done"/>
</state>The event name carries the block id, so two waits in the same chart never
wake each other. <send> names no target, which under spec 6.2.2 is
the running session's own external queue - and a delayed send on that
queue is exactly what statifier_oban turns into a durable timer. This
type still does not know durable timers exist; it emits an ordinary
delayed send and the host's session decides what backs it.
The send id rides the reserved role
The id is minted with Context.role_id/2 under
StatifierBlocks.Compiler.Cancels.armed_role/0, the same reserved role
core.send mints under, so StatifierBlocks.Compiler.Cancels reaches
this send as it reaches any other: a wait left before its delay elapses -
by an interrupt, by a losing complete: first lane, by an abandoned
group - has its timer cancelled in the enclosing scope's <onexit>. The
wait's own state bounds only what the interpreter holds; a delayed send
a durable host has already scheduled outlives the state that armed it
unless something cancels it.
The duration is compiled, not read out
The stored value is the author's own spelling, so the emitted delay
attribute is never simply those bytes: a predicator string is
canonicalised to the ISO pivot and rendered back out as the shorthand
Statifier.Duration reads, and a stored ISO value is already at the
pivot and only rendered. Both steps live in
StatifierBlocks.Core.Duration - to_iso/1 then to_delay/1, exactly
the pair core.send calls - which is why the component-to-unit table
that used to sit here is now in that module's moduledoc and nowhere
else. Two duration tables would be two grammars the day one of them was
edited.
The attribute is left unannotated for the reason core.send's emit
writes out: ADR-0004 decision 9 annotates an attribute whose value is
the author's verbatim, and these bytes are not - 1h30m and PT1H30M
both emit 1h30m.
A wait constrains nothing and is constrained by nothing beyond being a
step: it declares kinds and leaves consumes and produces to
ADR-0003 decision 5's permissive default, since waiting transforms no
data.