ehmry
/
syndicate-nim
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Generate patterns from ref types

This commit is contained in:
Emery Hemingway 2021-12-11 18:36:31 +00:00
parent ae04bc1019
commit f710419ead
1 changed files with 8 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
src/syndicate/patterns.nim
View File

@ -1,7 +1,7 @@
# SPDX-FileCopyrightText: ☭ 2021 Emery Hemingway # SPDX-FileCopyrightText: ☭ 2021 Emery Hemingway
# SPDX-License-Identifier: Unlicense # SPDX-License-Identifier: Unlicense
import std/[macros, tables] import std/[macros, tables, typetraits]
import preserves import preserves
import ./protocols/dataspacePatterns import ./protocols/dataspacePatterns
@ -29,13 +29,11 @@ proc `?`*(d: DCompound): Pattern =
proc `?`*(s: string): Pattern = proc `?`*(s: string): Pattern =
?DLit(value: toPreserve(s, Ref)) ?DLit(value: toPreserve(s, Ref))
proc arity(T: typedesc): int = proc drop*(): Pattern = Pattern(orKind: PatternKind.DDiscard)
var t: T # a hack to iterate the fields of a non-existent instance proc grab*(): Pattern = ?DBind(pattern: drop())
for _ in fields(t): inc result
proc `?_`*(): Pattern = Pattern(orKind: PatternKind.DDiscard) proc `?_`*(): Pattern = drop()
proc `?*`*(): Pattern = grab()
proc `?*`*(): Pattern = ?DBind(pattern: `?_`())
proc `?`*(T: typedesc; bindings: openArray[(int, Pattern)]): Pattern = proc `?`*(T: typedesc; bindings: openArray[(int, Pattern)]): Pattern =
## Pattern constructor operator. ## Pattern constructor operator.
@ -44,8 +42,10 @@ proc `?`*(T: typedesc; bindings: openArray[(int, Pattern)]): Pattern =
result = ?DCompound( result = ?DCompound(
orKind: DCompoundKind.rec, orKind: DCompoundKind.rec,
rec: DCompoundRec( rec: DCompoundRec(
ctor: CRec(label: label, arity: T.arity), ctor: CRec(label: label, arity: bindings.len),
members: toTable bindings)) members: toTable bindings))
elif T is ref:
`?`(pointerBase(T), bindings)
else: else:
{.error: "no custom pragma on " & $T.} {.error: "no custom pragma on " & $T.}