Evaluating#

An expression becomes a program before it runs. Expressions describes its values. Compilation and execution determine how it runs. The native API accepts documents for the program and its input variables.

Offset (hex)	Bytes (hex)	Meaning
000	54 52 4F 4E	magic TRON
004	3C 616765	txt "age"
008	02 24000000000000 00	i64 36
011	0F 0A 04000000 0800 0000	map leaf, size 10: @4 → @8
01B	4C 726F6C65	txt "role"
020	8C 656E67696E6565 72	txt "engineer"
029	0F 0A 1B000000 2000 0000	map leaf, size 10: @1B → @20
033	4C 6E616D65	txt "name"
038	3C 416461	txt "Ada"
03C	0F 0A 33000000 3800 0000	map leaf, size 10: @33 → @38
046	07 12 00910000 1100 0000 29000000 3C00 0000	map branch, size 18, depth 0 (root), slots 8, 12, 15: @11 → @29 → @3C
058	5C 236C696E6B	txt "#link"
05E	5C 235F616461	txt "#_ada"
064	0F 0A 58000000 5E00 0000	map leaf, size 10: @58 → @5E
06E	3C 616765	txt "age"
072	02 29000000000000 00	i64 41
07B	0F 0A 6E000000 7200 0000	map leaf, size 10: @6E → @72
085	6C 6D656E746F72	txt "mentor"
08C	0F 0A 85000000 6400 0000	map leaf, size 10: @85 → @64
096	4C 726F6C65	txt "role"
09B	8C 656E67696E6565 72	txt "engineer"
0A4	0F 0A 96000000 9B00 0000	map leaf, size 10: @96 → @9B
0AE	4C 6E616D65	txt "name"
0B3	3C 426F62	txt "Bob"
0B7	0F 0A AE000000 B300 0000	map leaf, size 10: @AE → @B3
0C1	07 16 00990000 7B00 0000 8C000000 A400 0000 B7000000	map branch, size 22, depth 0 (root), slots 8, 11, 12, 15: @7B → @8C → @A4 → @B7
0D7	3C 616765	txt "age"
0DB	02 1D000000000000 00	i64 29
0E4	0F 0A D7000000 DB00 0000	map leaf, size 10: @D7 → @DB
0EE	4C 726F6C65	txt "role"
0F3	8C 64657369676E65 72	txt "designer"
0FC	0F 0A EE000000 F300 0000	map leaf, size 10: @EE → @F3
106	4C 6E616D65	txt "name"
10B	2C 4379	txt "Cy"
10E	0F 0A 06010000 0B01 0000	map leaf, size 10: @106 → @10B
118	07 12 00910000 E400 0000 FC000000 0E01 0000	map branch, size 18, depth 0 (root), slots 8, 12, 15: @E4 → @FC → @10E
12A	4C 235F6379	txt "#_cy"
12F	0F 0A 2A010000 1801 0000	map leaf, size 10: @12A → @118
139	5C 235F626F62	txt "#_bob"
13F	0F 0A 39010000 C100 0000	map leaf, size 10: @139 → @C1
149	5C 235F616461	txt "#_ada"
14F	0F 0A 49010000 4600 0000	map leaf, size 10: @149 → @46
159	07 12 80210000 2F01 0000 3F010000 4F01 0000	map branch, size 18, depth 0 (root), slots 7, 8, 13: @12F → @13F → @14F
16B	59010000 00000000	root → @159; previous: none

Stored expressions#

A stored expression has a title and an authored program document. Saving it validates compilation. A successful definition commit records its new revision. An inline program needs no database. Both forms use the same evaluator.

Offset (hex)	Bytes (hex)	Meaning
00	54 52 4F 4E	magic TRON
04	1C 2B	txt "+"
06	2C 3F78	txt "?x"
09	02 01000000000000 00	i64 1
12	0E 15 00 0700 030000 00 04000000 060000 00 09000000	array leaf, size 21, shift 0, bitmap 0007, count 3 (root): @4 → @6 → @9
27	12000000 00000000	root → @12; previous: none

Offset (hex)	Bytes (hex)	Meaning
00	54 52 4F 4E	magic TRON
04	02 2A000000000000 00	i64 42
0D	04000000 00000000	root → @4; previous: none

Maximum cost#

The evaluation cost measures CPU time on the execution thread. The public API reports 100-nanosecond ticks. The cost limit uses the same unit. It includes input preparation, execution, native helpers and native result construction.

A positive limit permits execution until the evaluator detects that the budget is exhausted. Checks occur during execution and after result construction. A helper can cross the limit before the next check. Zero leaves a standalone evaluation without an explicit limit. Query budgets have additional rules in Bounds.

Errors#

Compilation rejects an unknown operator or an invalid argument count. Evaluation rejects an invalid value type, arithmetic overflow or division by zero. The native diagnostic identifies the error and gives its explanation.

Offset (hex)	Bytes (hex)	Meaning
00	54 52 4F 4E	magic TRON
04	1C 2F	txt "/"
06	02 01000000000000 00	i64 1
0F	02 00000000000000 00	i64 0
18	0E 15 00 0700 030000 00 04000000 060000 00 0F000000	array leaf, size 21, shift 0, bitmap 0007, count 3 (root): @4 → @6 → @F
2D	18000000 00000000	root → @18; previous: none

Run it#

build · program evaluate.