v/vlib/v
Ryan Prior 64e7c54884
v.util: accomodate reproducible build environments like guix, by not recompiling cmd/tools when mtime < 1024 (#7702)
2020-12-31 10:31:38 +02:00
..
ast parser: allow `const x = 0` consts outside of const blocks 2020-12-30 02:15:44 +01:00
builder v.pref: fix `-nocache`, add `-no-retry-compilation`, add `-d trace_use_cache` 2020-12-28 09:42:43 +02:00
cflag v: add VCACHE support for thirdparty object files and for `v build-module` 2020-10-25 03:09:07 +03:00
checker cgen: fix embed generic field access & method call (#7725) 2020-12-30 23:49:02 +01:00
depgraph fmt: fix multiple things and format most of the compiler (#6631) 2020-10-15 22:12:59 +02:00
doc fmt: unwrap long single line ifs (#7608) 2020-12-27 14:20:30 +01:00
errors fmt: fix multiple things and format most of the compiler (#6631) 2020-10-15 22:12:59 +02:00
eval all: refactor UnionSumType to SumType (#6944) 2020-11-25 13:09:40 +02:00
fmt fmt: fix a space in const decl 2020-12-30 02:24:38 +01:00
gen cgen: fix multi return auto str methods. closes #7726 2020-12-31 10:21:02 +11:00
parser parser: proper error on fn decl in script mode (#7680) 2020-12-30 21:18:36 +02:00
pkgconfig pkgconfig: improve and fix the parser; move to v.pkgconfig (#6695) 2020-10-29 11:57:23 +02:00
pref v run: pass all args after file.v only to script args, do not process them as v flags (#7672) 2020-12-29 21:16:20 +02:00
scanner fmt: keep _ separator in number literals (#7495) 2020-12-23 14:48:43 +02:00
table all: re-implement variadics using arrays & implement array decomposition to varg (#7689) 2020-12-29 16:14:08 +01:00
tests cgen: fix multi return auto str methods. closes #7726 2020-12-31 10:21:02 +11:00
token parser: add information about the ending line for a few elements (#7414) 2020-12-22 14:45:12 +01:00
util v.util: accomodate reproducible build environments like guix, by not recompiling cmd/tools when mtime < 1024 (#7702) 2020-12-31 10:31:38 +02:00
vcache builder: use the same compilation mode for thirdparty object files (#7450) 2020-12-21 17:46:26 +01:00
vet fmt: make single-stmt `or` blocks single-line (#7126) 2020-12-04 13:25:23 +02:00
vmod checker: arr1=arr2 warning 2020-12-20 10:42:46 +01:00
README.md check-md: verify code example formatting (#7143) 2020-12-05 22:54:41 +01:00
compiler_errors_test.v ci: fix compilation of the test infrastructure 2020-12-20 18:27:42 +02:00

README.md

Compiler pipeline

A simple high level explanation how the compiler pipeline (parser -> checker -> generator) works.

Reading files

Getting builtin files

To load all builtin files, a preference Preferences.lookup_path for the path where to look for exists. See Builder.get_builtin_files as example. If the file is a .vsh file and the backend is C, vlib/os will also be loaded as builtin.

Getting project files

Either there is a specific file: my_file.v or a directory containing V files. In the last case it scans that directory for all files. See Builder.v_files_from_dir as the helper method. This list of files needs to be filtered so that only *.v files exist.

Skips the following file types:

  • *_test.v
  • either *.c.v or *.c.js depending on the backend
  • all files that doesn't end with .v
  • Files that are not defined in Preferences.compile_defines or Preferences.compile_defines_all if any file is defined.

Parsing files

To parse something a new template is created as the first step:

import v.table

table := table.new_table()

a new preference is created:

import v.pref

pref := pref.Preferences{}

and a new scope is created:

import v.ast

scope := ast.Scope{
	parent: 0
}

after that, you can parse your files.

Parse text

If you want to parse only text which isn't saved on the disk you can use this function.

import v.parser

code := ''
// table, pref and scope needs to be passed as reference
parsed_file := parser.parse_text(code, table, .parse_comments, &pref, &scope)

Parse a single file

For parsing files on disk, a path needs to be provided. The paths are collected one step earlier.

import v.parser

path := ''
// table, pref and scope needs to be passed as reference
parsed_file := parser.parse_file(path, table, .parse_comments, &pref, &scope)

Parse a set of files

If you have a batch of paths available which should be parsed, there is also a function which does all the work.

import v.parser

paths := ['']
// table, pref and scope needs to be passed as reference
parsed_files := parser.parse_files(paths, table, &pref, &scope)

Parse imports

A file often contains imports. These imports might need to be parsed as well. The builder contains a method which does this: Builder.parse_imports.

If the module which is imported isn't parsed already, you have to collect it relatively from the main file. For this the ast.File contains a list of imports. Those imports needs to be found on disk. . is just replaced with seperators in the relative location of the main file. Then all files from that directory are collected and parsed again like the previous steps explained.

Checking AST

A new checker is created:

import v.checker

mut checker := checker.new_checker(table, &pref)

After checking your files in checker.errors and checker.warnings you can see the results.

Check ast.File

checker.check(parsed_file)

Check a list of ast.File

checker.check_files(parsed_files)

Generate target from AST

Generating C code works just as this:

import v.gen

res := gen.cgen(parsed_files, table, &pref)