Provisional API: This reference documents current compiler behavior. Compatibility is not yet promised.

src/stage.x

The values crossing between meta code and the program.

Functions

Functions

literal_text_value

Var literal_text_value(String spelling)

Returns the value of a String or character literal from its source spelling, quotes included: adjacent pieces are unescaped on their own and joined, as C does, and a character is its code.

Source: src/stage.x:213

Compiler

Compiler.check_meta_call

void Compiler.check_meta_call(Compiler c, List callee, Token origin)

Refuses a run-time call to a meta function this compiler derived compile-time only.

Such a function reaches a Meta operation, so it exists only inside a compiler and the unit emits no definition for it. Unchecked, the call reaches the linker as an undefined symbol, which names the C spelling and not the source. Another meta function may call it: calling one is what makes the caller compile-time only too, so a body being parsed under the marker is left alone.

Source: src/stage.x:448

Compiler.folded_constant

Var Compiler.folded_constant(Compiler c, Var node)

Returns the value of the folded constant node, or void when part of it is only known at run time. Literal folding hoists a constant into the compiler cache and leaves (cache ID), a graph of ids over cons, var and string leaves.

Source: src/stage.x:139

Compiler.meta_argument

Var Compiler.meta_argument( Compiler c, List node, Type want, Token site, MetaCall call)

Returns the value the argument expression node of a $ call passes to a parameter of type want, or of no declared type when want is NULL: a constant, captured syntax, or the result of another $ call, which call evaluates. Captured literal syntax reaches a parameter that is not syntax as the literal’s value, a TypeInfo parameter as the description of its type, and a Source parameter with its source text. Anything else is reported at site.

Source: src/stage.x:64

Compiler.meta_is_comptime_only

int Compiler.meta_is_comptime_only(Compiler c, List fn)

Returns whether fn is a meta function this compiler recorded as compile-time only, whose runtime form the unit does not emit.

Source: src/stage.x:459

Compiler.meta_value_expression

List Compiler.meta_value_expression( Compiler c, Type declared, Var value, Token site)

Returns literal code for a compile-time value, preserving declared when supplied. An Array or Map, at any depth, becomes a literal that builds a fresh collection on every execution; other data comes from the literal cache. A cycle or a collection held twice is reported at site. Returns NULL for code Lists or values without a literal representation.

Source: src/stage.x:241

Design notes

This file owns what crosses between meta code and the program: the arguments a $ call passes, evaluated from constants, captured syntax, and other $ calls; the literal code a result becomes; and the rule that a function reaching a compiler operation has no runtime form. A unit’s meta group and its emission are in meta-group.x; the compiler’s side of the project helper is in meta-helper-client.x.