Module formula_highlight 

Pure syntax highlighting for the formula editor: &str -> LayoutJob.

A small independent char-class scanner (identifiers / numbers / strings / date literals / operators), good enough for visually useful highlighting — it does not need to match core_model::parser’s exact grammar. Kept free of any egui::Ui access so it’s unit-testable without a window.

Structs

Token

One scanned token: its kind and byte range in the source text.

Enums

TokenKind

The lexical class of one highlighted token.

Constants

ERROR_COLOR

The color of formula error text and of the error-position underline. The palette has no red, so an error is marked by the underline, not by hue.

ERROR_UNDERLINE 🔒

The error-position underline: thicker than a text underline so it reads.

FUNCTIONS 🔒

A known scalar/aggregation function name, highlighted distinctly from a plain measure/category identifier.

Functions

char_at 🔒

The character at byte offset i of text. i must be a char boundary (every offset scan advances to is one, by construction).

color_for 🔒

Token colors, within the NeXTSTEP grayscale palette (theme.rs): names, functions and numbers in black on the white field, operators and literals in dark gray (7.5:1 on white).

highlight_formula

Build a highlighted [LayoutJob] for text, coloring tokens per scan/color_for. If error is Some(start..end), those bytes (clamped to the text and to char boundaries; a span may cover part of a token or several) are rendered in ERROR_COLOR with a 2 px underline so the error’s location is visible inline. crate::diagnostics places it: the token at a parse error’s position, or the name a compile error names.

scan

Scan text into a flat sequence of Tokens covering every byte (no gaps), classifying identifiers/numbers/strings/date-literals/operators by simple char class. Never fails — unrecognized characters become single-char Operator tokens so the whole string is always covered.