Outline of docs for clauses, operators, and special syntax

doc/clause-reference.md

@@ -0,0 +1,38 @@
+# SQL Clauses Supported
+
+This section lists all the SQL clauses that HoneySQL
+supports out of the box, in the order that they are
+processed for formatting.
+
+Clauses can be specified as keywords or symbols. Use
+`-` in the clause name where the formatted SQL would have
+a space (e.g., `:left-join` is formatted as `LEFT JOIN`).
+
+Except as noted, these clauses apply to all the SQL
+dialects that HoneySQL supports.
+
+## nest
+## with, with-recursive
+## intersect, union, union-all, except, except-all
+## select, select-distinct
+## insert-into
+## update
+## delete, delete-from
+## truncate
+## columns
+## set (ANSI)
+## from
+## using
+## join, left-join, right-join, inner-join, outer-join, full-join
+## cross-join
+## set (MySQL)
+## where
+## group-by
+## having
+## order-by
+## limit, offset (MySQL)
+## for
+## lock (MySQL)
+## values
+## on-conflict, on-constraint, do-nothing, do-update-set
+## returning

doc/cljdoc.edn

@@ -1,5 +1,9 @@
-{:cljdoc.doc/tree [["Readme" {:file "README.md"}]
+{:cljdoc.doc/tree
+ [["Readme" {:file "README.md"}]
   ["Changes" {:file "CHANGELOG.md"}]
   ["Getting Started" {:file "doc/getting-started.md"}
+   ["SQL Clause Reference" {:file "doc/clause-reference.md"}]
+   ["SQL Operator Reference" {:file "doc/operator-reference.md"}]
+   ["SQL 'Special Syntax'" {:file "doc/special-syntax.md"}]
    ["Extending HoneySQL" {:file "doc/extending-honeysql.md"}]]
   ["Differences from 1.x" {:file "doc/difference-from-1-x.md"}]]}

doc/extending-honeysql.md

@@ -16,6 +16,30 @@ Built in functions (special syntax) include: `:array`, `:case`,
 
 ## Registering a New Clause Formatter
 
+`honey.sql/register-clause!` accepts a keyword (or a symbol)
+that should be treated as a new clause in a SQL statement,
+a "formatter", and a keyword (or a symbol) that identifies
+an existing clause that this new one should be ordered before.
+
+The formatter can either be a function
+of two arguments or a previously registered clause (so
+that you can easily reuse formatters).
+
+The formatter function will be called with:
+* The function name (always as a keyword),
+* The sequence of arguments provided.
+
+The third argument to `register-clause!` allows you to
+insert your new clause formatter so that clauses are
+formatted in the correct order for your SQL dialect.
+For example, `:select` comes before `:from` which comes
+before `:where`. This is the most implementation-specific
+part of extending HoneySQL because you'll need to look at
+the (private) Var `default-clause-order` in `honey.sql`
+for guidance. _[I plan to add a section in the documentation
+somewhere that lists built-in clauses in order which this
+can link to...]_
+
 ## Registering a New Operator
 
 `honey.sql/register-op!` accepts a keyword (or a symbol) that
@@ -58,7 +82,7 @@ and a "formatter". The formatter can either be a function
 of two arguments or a previously registered "function" (so
 that you can easily reuse formatters).
 
-The formatter will be called with:
+The formatter function will be called with:
 * The function name (always as a keyword),
 * The sequence of arguments provided.
 

doc/operator-reference.md

@@ -0,0 +1,58 @@
+# SQL Operators Supported
+
+This section lists the operators that HoneySQL supports
+out of the box. There is no operator precedence assumed
+because SQL expressions are represented in prefix form,
+just like Clojure expressions.
+
+Operators can be specified as keywords or symbols. Use
+`-` in the operator where the formatted SQL would have
+a space (e.g., `:not-like` is formatted as `NOT LIKE`).
+
+## and, or
+
+Boolean operators. May take any number of expressions
+as arguments. `nil` expressions are ignored which can
+make it easier to programmatically build conditional
+expressions (since an expression that should be omitted
+can simply evaluate to `nil` instead).
+
+```clojure
+{...
+ :where [:and [:= :type "match"]
+              (when need-status [:in :status [1 5]])]
+ ...}
+;; if need-status is truthy:
+;;=> ["...WHERE (type = ?) AND (status IN (?, ?))..." "match" 1 5]
+;; or, if need-status is falsey:
+;;=> ["...WHERE (type = ?)..." "match"]
+{...
+ :where [:or [:= :id 42] [:= :type "match"]]
+ ...}
+;;=> ["...WHERE (id = ?) OR (type = ?)..." 42 "match"]
+```
+
+## = <> < > <= >=
+
+Binary comparison operators. These expect exactly
+two arguments.
+
+The following aliases are also supported:
+* `is` -- an alias for `=`
+* `is-not`, `not=`, `!=` -- aliases for `<>`
+
+## mod, xor, + - * / % | & ^
+
+Mathematical and bitwise operators. `+` and `*` are
+variadic; the rest are strictly binary operators.
+
+## like, not like, ilike, not ilike, regexp
+
+Pattern matching binary operators. `regex` is accepted
+as an alias for `regexp`.
+
+`similar-to` and `not-similar-to` are also supported.
+
+## ||
+
+Variadic string concatenation operator.

doc/special-syntax.md

@@ -0,0 +1,19 @@
+# SQL Special Syntax
+
+This section lists the function-like expressions that
+HoneySQL supports out of the box which are formatted
+as special syntactic forms.
+
+## array
+## between
+## case
+## cast
+## composite
+## default
+## inline
+## interval
+## lift
+## nest
+## not
+## param
+## raw

src/honey/sql.cljc

@@ -810,7 +810,8 @@
   only clause so far where that would matter is `:set` which differs in
   MySQL."
   [clause formatter before]
-  (let [clause (sym->kw clause)]
+  (let [clause (sym->kw clause)
+        before (sym->kw before)]
     (assert (keyword? clause))
     (let [k (sym->kw formatter)
           f (if (keyword? k)
@@ -891,6 +892,8 @@
                     :pretty true}))
   ;; while working on the docs
   (require '[honey.sql :as sql])
+  (sql/format {:where [:and [:= :id 42] [:= :type "match"]]})
+  (sql/format {:where [:and [:= :type "match"] (when false [:in :status [1 5]])]})
   (sql/format {:select [:*] :from [:table] :where [:= :id 1]})
   (sql/format {:select [:t/id [:name :item]], :from [[:table :t]], :where [:= :id 1]})
   (sql/format '{select [t/id [name item]], from [[table t]], where [= id 1]})