Choose one ternary syntax: braced vs prefix

[danieljohnmorris]

Problem

We currently have two ternary syntaxes that do the same thing:

=x 0{10}{20}     -- braced ternary (original)
?=x 0 10 20      -- prefix ternary (new in v0.9.1)

Both are 5 tokens. Having two ways to do the same thing violates ilo's core principle of minimal surface area — one way to do each thing.

Options

Keep braced, drop prefix

• =x 0{10}{20} is consistent with guards (braces = body)
• Already established, documented, used in examples
• Braces visually delimit the two branches
• No ? overloading (already used for match)

Keep prefix, drop braced

• ?=x 0 10 20 is more consistent with prefix notation style
• No braces needed
• But ? is already overloaded (match expressions)
• ?= can look like assignment at a glance

Decision needed

Pick one and remove the other from the parser, SPEC, and docs.