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During tree construction, internal lookup tables control the rendering
transformations. You can add to them using procedure qcons-declare!
.
Declare as part of category (a keyword) the symbol x. extra information may be required for the particular category. Currently, these categories are recognized:
#:infix
Render (x A B ...)
as ( A x B x ...)
.
#:postfix
Render (x A)
as ( A x )
.
#:display-alias
Render x
as something else. extra is a string
that specifies what to display instead of x. For example,
null?
and not-null?
are pre-declared to render as
IS NULL
and IS NOT NULL
, respectively.
#:keyword-args-ok
Render (x A B ...)
as x (A, B, ...)
if none
of A
, B
, … are keywords. In the presence
of keywords, render it as x (A B ...)
, without any commas
in the argument list.
The rest of this section presents various lists of built-in declarations.
Using qcons-declare!
on a built-in symbol overwrites the associated
value (if any). There is no undeclare support.
These are the infix operators.
|| ||/ |/ / !! % ^ * - + @ & | << >> && &< &> <-> <^ >^ ?- ?-| @-@ ?| ?|| @@ ~= <<= >>= # ## ?# = < <= > >= <> != all any in like not-like ilike not-ilike ~~ !~~ ~~* !~~* similar not-similar ~ ~* !~ !~*
These are the postfix operators.
! null? not-null? true? not-true? false? not-false? unknown? not-unknown?
Display aliases exist for these symbols.
null? not-null? true? not-true? false? not-false? unknown? not-unknown? not-like not-ilike similar not-similar
These functions render differently depending on the presence of keyword args.
substring trim extract convert overlay position
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