The PeachQ REPL¶

Use PeachQ interactively in a native terminal or in the browser REPL. Both evaluate q expressions. The native executable supplies the terminal editor; the website supplies its own browser editor and controls.

Reading tables¶

PeachQ's default native console separates table columns with vertical bars and shows types under their names. Key columns have an equals-sign separator. A mixed column has no single type label; values within it retain useful type distinctions.

This transcript shows a keyed table with a nested column. The q) prefix marks the command entered; the lines below it are the output:

q)([instrument:`ALPHA`BETA]quantity:10 20;price:12.5 18.0;levels:(1 2;3 4))
| instrument | quantity | price | levels |
| symbol     | long     | float |        |
|============|----------|-------|--------|
| ALPHA      | 10       | 12.5  | 1 2    |
| BETA       | 20       | 18    | 3 4    |

The instrument column is the key; quantity is long and price is float. The nested levels column contains a list in each row. Formatting depends on console width and runtime version; the table's data does not depend on its presentation.

For mixed nested values:

q)([]name:`first`second;levels:(1 2;3 4f))
| name   | levels |
| symbol |        |
|--------|--------|
| first  | 1 2    |
| second | 3 4f   |

The float suffix helps distinguish the second row's values from integers.

The native -classic launch flag selects the legacy q-style table display and a cleaner starting environment. It is not a switch that removes every language difference. See command-line options.

Editing in the native terminal¶

History and line editing are built in; a separate rlwrap is unnecessary.

Key	Action
Up / Down	Browse previous commands
Ctrl-R	Search command history
Home / End	Move to the beginning / end of the line
Ctrl-Left / Ctrl-Right	Move by word
Ctrl-W	Delete the word before the cursor
Ctrl-U	Clear the line
Tab	Complete a name

The editor offers inline completion suggestions. History is saved in .qhist under your home directory, with a current-directory fallback when no home directory is available. Enter \? for the help entry point.

Syntax highlighting¶

The native terminal colours q as you type: builtin keywords, strings and their escapes, comments, symbols, numbers, dates, times and nulls, operators, system names such as .z.p and -8!, and \ commands. With the cursor on or inside a bracket or quote, the matching pair is highlighted too.

Colour depends only on the text you type. A builtin looks the same with or without its namespace, so count and .q.count match. Your own variables are left uncoloured.

Changing the colours¶

The palette is the dictionary .pq.hl, mapping each role to a colour:

Role	Colours	Role	Colours
`kw`	keywords	`tmp`	dates, times, nulls
`str`	strings	`op`	operators and iterators
`esc`	string escapes	`sys`	system names
`cmt`	comments	`cmd`	`\` commands
`sym`	symbols	`match`	matching bracket or quote
`num`	numbers

A value is a 256-colour index (0–255), or a terminal SGR string such as "1;38;5;141" for bold or other effects. Set it in your QINIT startup file so it applies to every session:

.pq.hl[`kw]:141          / keywords in violet
.pq.hl[`cmt]:"3;38;5;244" / comments in grey italics

Roles you don't set keep their defaults, and an invalid value falls back to its role's default. \?.pq.hl shows the current reference.

Turning colour off¶

Set NO_COLOR (any non-empty value) or PEACHQ_COLORS=0 in the environment before starting PeachQ. This turns off all console colour, including highlighting. PEACHQ_COLORS=1 forces colour on, even when NO_COLOR is set.

In the browser¶

Try Live loads a WebAssembly runtime and evaluates expressions locally in your tab.