Refine detection of procedure declarations

[istathar]

Two interacting problems have been dogging us for some time. Detection of procedures has been fraught because : can appear both in procedure declarations and in normal prose. The Technique parser is built around the capturing ranges at the current contextual scope, so depends on accurately scanning from one procedure to the next, so being able to find those correctly and avoiding false positives is crucial to both correctness and being able to offer good error messages.

The solution is to make a slight change to the grammar as follows. A procedure declaration is an identifier, followed by space (at least one), followed by a colon : (then optionally followed by a signature).

The presence of the space between identifier and colon allows us to differentiate between a procedure definition

warning :

and prose in a procedure description

Warning: be warned!

The second problem addressed by this branch is ensuring characters in literal (especially strings literals and multi-line string literals) are masked and preserved as part of the literal and not considered as being language syntax. This also has been a few rounds; in particular colon : and quote ' characters kept false matches for other predicates. This branch improves the scanner to track text vs quoted vs fenced runs as it works through the input.

[istathar]

Implements

• Refine definition of procedure declaration specification#16