Module functions 

The built-in function registry: ONE table for every function the formula language knows, read by the parser (names, aliases, arity), the compiler (argument and result types, kind), the GUI and CNL (spellings), and the generated function reference (docs/src/functions.md).

Evaluation lives in the engine (improv_engine::builtins); a test there walks all and fails if any evaluable id has no implementation.

A FuncId is persisted in every stored formula, so ids are stable forever: never renumber or reuse one. Aliases resolve to their canonical id at parse time, so stored formulas never hold an alias.

Structs

FnDef

One built-in function.

Enums

Arg

An argument’s type.

Category

A function’s documentation category (groups the reference page).

Kind

How a function is compiled.

Over

Which arguments of an aggregation are reduced over the OVER categories.

Ret

What a function returns.

Constants

INTO

The reserved id of an INTO Category clause: an array function’s trailing argument Call(INTO, [Category(K)]) (SORT(x OVER T INTO K)).

LAMBDA_SLOTS

The highest placeholder id; ids above LAMBDA_SLOTS - 2048 are reserved.

NAMED_LAMBDA_BASE

The first function id of a named LAMBDA call: lambda id is called as FuncId(NAMED_LAMBDA_BASE + id). Above every built-in.

POSITION

POSITION(T): an item’s 1-based position along its category.

WHERE

The reserved id of a WHERE clause: an aggregation’s trailing argument Call(WHERE, [predicate]) (SUM(x OVER T WHERE x > 0)). Not a callable function, so not in the registry.

WINDOW

The reserved id of a window: an aggregation’s trailing argument Call(WINDOW, [from, to]) (SUM(x OVER T[FIRST..THIS])). Each bound is a number (an offset from this item; 0 is THIS) or the text FIRST / LAST.

Statics

CORE

The P1 core: aggregations, logical, information, math, rounding, text. Order is documentation order within a category.

Functions

aggregation

The aggregation (or per-item reduction) a name means, if any.

all

Every built-in function.

by_id

The function with id id.

by_name

The functions a name (canonical or alias, case-insensitive) can mean: an aggregation and its scalar twin share a name (SUM(x OVER T) vs SUM(a, b)), so a name maps to at most one of each Kind.

call_at

Where the caret sits in a call: the innermost unclosed NAME( before byte offset caret in text, and the 0-based argument it is in. Strings and nested parentheses are skipped. Signature help uses it.

callable

The non-aggregating function a name means, if any.

closest

Up to n function names closest to word by edit distance (a typo’s likely meaning), nearest first; only those within a third of its length, at least 2.

complete

Function names (canonical and aliases) starting with prefix (case-insensitive), canonical first, for completion.

edit_distance

Levenshtein distance over chars.

is_aggregation

Whether id reduces over OVER categories.

lambda_category

The category standing for parameter i of a named LAMBDA whose body uses the parameter as a category (MAX(x OVER c), POSITION(c)).

lambda_category_of

The parameter index of a category placeholder (see lambda_category).

lambda_param

The reference standing for parameter i in a named LAMBDA’s body.

lambda_param_of

The parameter index of a placeholder id (see lambda_param).

lambda_slot

The placeholder measure id for parameter i (0 the accumulator, 1 the value) of the k-th REDUCE/SCAN lambda in a formula. Placeholders sit at the top of the id space, above any real measure.

lambda_slot_of

The (k, i) of a placeholder id (see lambda_slot).

named_lambda

The function id a call of named LAMBDA id is stored as.

named_lambda_of

The named LAMBDA a function id calls, if it is one.

over

d with its reduced arguments.

reference_markdown

The function reference page (docs/src/functions.md), generated from all so the docs cannot drift from the code. A test compares it with the committed file; UPDATE_DOCS=1 cargo test -p improv_core_model rewrites it.

search

Functions matching query, best first: an exact name or alias, then a prefix, then a word of the name or description. Case-insensitive; an empty query lists everything by name. The help browser’s search and the formula editor’s completion both use this.