Nesting & Termination

OPEN and CLOSE define blocks in OcaltQL. They are used by IF, WHILE, LOOP, SWITCH, and NEW OPERATION. Blocks can nest to any depth. Variable scope is shared across control-flow blocks — variables set inside an IF, WHILE, LOOP, or SWITCH are available outside it. A NEW OPERATION body is the one exception — it runs in its own isolated frame, covered below.

Inline References

Square brackets [ and ] mark an inline reference — an expression that resolves to a value at the point where a value is expected. Anything that would normally require an intermediate variable and a separate AFTER step can be written inline instead. Inline references are nestable: the innermost resolves first, then outward.

Simple
EMIT [CALCULATE 1 + 1]
(* Output: 2 *)
Nested
NEW OPERATION square WITH ?n
OPEN
  RETURN [CALCULATE ?n * ?n]
CLOSE

AFTER EMIT [CALCULATE [RUN square WITH 4] + [RUN square WITH 3]]
(* [RUN square WITH 4] resolves to 16 *)
(* [RUN square WITH 3] resolves to 9  *)
(* Output: 25 *)

OPEN and CLOSE

Every block-level construct in OcaltQL uses OPEN and CLOSE as its delimiters. There are no curly braces. There are no indentation rules. OPEN begins the block and CLOSE ends it.

IF Block
IF ?a IS GREATER THAN 10
OPEN
  EMIT "big"
CLOSE
WHILE Block
NUMBER 0 SET ?i
AFTER WHILE ?i IS LESS THAN 5
OPEN
  EMIT ?i
  AFTER CALCULATE ?i + 1 SET ?i
CLOSE
LOOP Block
LOOP 1 TO 5 SET ?i
OPEN
  EMIT ?i
CLOSE
NEW OPERATION Block
NEW OPERATION myfunc WITH ?x
OPEN
  CALCULATE ?x * 2 SET ?result
  AFTER RETURN ?result
CLOSE

Nested Blocks

Blocks nest to any depth. Any block-level construct can appear inside any other, with the exception that NEW OPERATION cannot contain another NEW OPERATION.

IF Inside LOOP
LOOP 1 TO 10 SET ?i
OPEN
  IF ?i IS GREATER THAN 5
  OPEN
    EMIT "big: " & ?i
  CLOSE
  OR
  OPEN
    EMIT "small: " & ?i
  CLOSE
CLOSE
LOOP Inside IF
IF ?flag IS SET
OPEN
  LOOP 1 TO 3 SET ?j
  OPEN
    EMIT ?j
  CLOSE
CLOSE
NEW OPERATION cannot be defined inside another NEW OPERATION. Operations are top-level definitions. All other block types can nest freely.

Variable Scope

OcaltQL does not have block-level variable isolation for control-flow blocks. Variables set inside an IF, WHILE, LOOP, or SWITCH are available outside it. Variables from the outer scope are accessible inside any of these blocks. Scope is flat across the entire script execution — with one exception: a NEW OPERATION body runs in its own isolated frame. Parameters and any variable set inside the operation are local to that call and disappear when it ends; only a RETURN value escapes. To write a value from inside an operation back out to the wider execution, use !GLOBAL('key') — see Header & Globals and Operations & Return.

Operation Frames Are Isolated
NEW OPERATION set_local
OPEN
  STRING "only visible in here" SET ?local
CLOSE
AFTER RUN set_local
AFTER EMIT ?local
(* Output: null — ?local was set inside the operation's own frame and does not escape it *)
Scope is Shared
IF true
OPEN
  STRING "inside" SET ?inner
CLOSE
AFTER EMIT ?inner
(* Output: "inside" — variable set inside a block is accessible outside it *)
Outer Variable Accessible Inside a Block
STRING "outer" SET ?out
AFTER IF true
OPEN
  EMIT ?out
CLOSE
(* Output: "outer" *)

SWITCH

SWITCH matches a variable against CASE values. Each CASE falls through to the next unless terminated with BREAK. DEFAULT is the fallback when no case matches.

Basic SWITCH
SWITCH ?status
OPEN
  CASE "pending"
    EMIT "Order is pending"
    BREAK

  CASE "shipped"
    EMIT "Order is shipped"
    BREAK

  CASE "delivered"
    EMIT "Order is delivered"
    BREAK

  DEFAULT
    EMIT "Unknown status"
    BREAK
CLOSE
Fallthrough — No BREAK
SWITCH ?grade
OPEN
  CASE "A"
  CASE "B"
    EMIT "Passing"
    BREAK

  CASE "C"
    EMIT "Barely passing"
    BREAK

  CASE "D"
  CASE "F"
    EMIT "Failing"
    BREAK

  DEFAULT
    EMIT "Invalid"
    BREAK
CLOSE
(* "A" and "B" both fall through to "Passing" *)
(* "D" and "F" both fall through to "Failing" *)
SWITCH with RETURN Inside Operation
NEW OPERATION get_color WITH ?status
OPEN
  SWITCH ?status
  OPEN
    CASE "pending"
      RETURN "yellow"
      BREAK

    CASE "shipped"
      RETURN "blue"
      BREAK

    CASE "delivered"
      RETURN "green"
      BREAK

    DEFAULT
      RETURN "gray"
      BREAK
  CLOSE
CLOSE
AFTER RUN get_color WITH "shipped" SET ?color
AFTER EMIT ?color
(* Output: blue *)

SWITCH on Multivariables

When SWITCH operates on a multivariable, each branch of the multivariable is evaluated independently against the cases in parallel. The result of each branch follows the same multivariable rules — the output is itself a multivariable if SET is used inside the cases.

Multivariable SWITCH
FETCH "https://api1.com/data" SET ?response AND FETCH "https://api2.com/data" SET ?response
AFTER WAIT FOR ?response

AFTER SWITCH ?response
OPEN
  CASE "success"
    STRING "won" SET ?result
    BREAK

  CASE "failed"
    STRING "lost" SET ?result
    BREAK

  DEFAULT
    STRING "unknown" SET ?result
    BREAK
CLOSE
AFTER COLLAPSE ?result SET ?all
AFTER FOREACH ?all SET ?item
OPEN
  EMIT ?item
CLOSE

Termination

OcaltQL has four termination controls. Each operates at a different level of the execution stack.

RETURN — Ends Operation or Script
NEW OPERATION early WITH ?a
OPEN
  IF ?a IS EQUAL TO 0
  OPEN
    RETURN "zero"
    (* Ends operation here *)
  CLOSE
  AFTER EMIT "non-zero"
CLOSE

RUN early WITH 0 SET ?r
AFTER EMIT ?r
(* Output: zero *)
RETURN — Non-Zero Path
NEW OPERATION early WITH ?a
OPEN
  IF ?a IS EQUAL TO 0
  OPEN
    RETURN "zero"
  CLOSE
  AFTER EMIT "non-zero"
CLOSE
AFTER RUN early WITH 5
(* Output: non-zero *)
BREAK — Exits Current Loop
LOOP 1 TO 10 SET ?i
OPEN
  IF ?i IS EQUAL TO 5
  OPEN
    BREAK
  CLOSE
  AFTER EMIT ?i
CLOSE
(* Output: 1 2 3 4 — exits before 5 *)
CONTINUE — Skips to Next Iteration
LOOP 1 TO 5 SET ?i
OPEN
  IF ?i IS EQUAL TO 3
  OPEN
    CONTINUE
  CLOSE
  AFTER EMIT ?i
CLOSE
(* Output: 1 2 4 5 — skips 3 *)
EXIT — Terminates Entire Script
EMIT "step 1"
AFTER EXIT
AFTER EMIT "never reached"
(* Script ends at EXIT *)
EXIT with HTTP Status Code
EXIT 404
(* Sets HTTP response status to 404 and ends script *)
Termination summary:
RETURN — ends the current operation or script, optionally with a value.
BREAK — exits the current loop or SWITCH case.
CONTINUE — skips to the next loop iteration.
EXIT — terminates the entire script, optionally with an HTTP status code.
Execution States →