Files
mgmt/lang/lexer.nex
James Shubin 400b58c0e9 lang: Improve string interpolation
The original string interpolation was based on hil which didn't allow
proper escaping, since they used a different escape pattern. Secondly,
the golang Unquote function didn't deal with the variable substitution,
which meant it had to be performed in a second step.

Most importantly, because we did this partial job in Unquote (the fact
that is strips the leading and trailing quotes tricked me into thinking
I was done with interpolation!) it was impossible to remedy the
remaining parts in a second pass with hil. Both operations needs to be
done in a single step. This is logical when you aren't tunnel visioned.

This patch replaces both of these so that string interpolation works
properly. This removes the ability to allow inline function calls in a
string, however this was an incidental feature, and it's not clear that
having it is a good idea. It also requires you wrap the var name with
curly braces. (They are not optional.)

This comes with a load of tests, but I think I got some of it wrong,
since I'm quite new at ragel. If you find something, please say so =D In
any case, this is much better than the original hil implementation, and
easy for a new contributor to patch to make the necessary fixes.
2021-02-17 03:35:12 -05:00

417 lines
9.4 KiB
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/[ \t\n]/ { /* skip over whitespace */ }
/{/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return OPEN_CURLY
}
/}/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return CLOSE_CURLY
}
/\(/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return OPEN_PAREN
}
/\)/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return CLOSE_PAREN
}
/\[/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return OPEN_BRACK
}
/\]/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return CLOSE_BRACK
}
/if/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return IF
}
/else/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return ELSE
}
/\?:/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return ELVIS
}
/=>/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return ROCKET
}
/,/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return COMMA
}
/:/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return COLON
}
/;/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return SEMICOLON
}
/=/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return EQUALS
}
/\+/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return PLUS
}
/\-/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return MINUS
}
/\*/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return MULTIPLY
}
/\// {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return DIVIDE
}
/==/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return EQ
}
/!=/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return NEQ
}
/</ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return LT
}
/>/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return GT
}
/<=/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return LTE
}
/>=/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return GTE
}
/&&/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return AND
}
/\|\|/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return OR
}
/!/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return NOT
}
/in/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return IN
}
/\->/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return ARROW
}
/\./ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
// sanity check... these should be the same!
if x, y := lval.str, interfaces.ModuleSep; x != y {
panic(fmt.Sprintf("DOT does not match ModuleSep (%s != %s)", x, y))
}
return DOT
}
/\$/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return DOLLAR
}
/bool/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return BOOL_IDENTIFIER
}
/str/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return STR_IDENTIFIER
}
/int/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return INT_IDENTIFIER
}
/float/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return FLOAT_IDENTIFIER
}
/map/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return MAP_IDENTIFIER
}
/struct/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return STRUCT_IDENTIFIER
}
/func/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return FUNC_IDENTIFIER
}
/class/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return CLASS_IDENTIFIER
}
/include/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return INCLUDE_IDENTIFIER
}
/import/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return IMPORT_IDENTIFIER
}
/as/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return AS_IDENTIFIER
}
/variant/ {
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return VARIANT_IDENTIFIER
}
/true|false/ {
yylex.pos(lval) // our pos
s := yylex.Text()
if s == "true" {
lval.bool = true
} else if s == "false" {
lval.bool = false
} else {
// the lexer was wrong
panic(fmt.Sprintf("error lexing BOOL, got: %s", s))
}
return BOOL
}
/"(\\.|[^"])*"/
{ // This matches any number of the bracketed patterns
// that are surrounded by the two quotes on each side.
// The bracket pattern is any escaped char or something
// that is not a single quote char. See this reference:
// https://www.lysator.liu.se/c/ANSI-C-grammar-l.html#STRING-LITERAL
// old: /"[\a\b\t\n\v\f\r !#$%&'()*+,-.\/0-9:;<=>?@A-Z\[\\\]^_a-z{|}~]*"/
yylex.pos(lval) // our pos
s := yylex.Text()
if s[0:1] != "\"" || s[len(s)-1:] != "\"" {
// unhandled error
panic(fmt.Sprintf("error lexing STRING, got: %s", s))
//return ERROR // unreachable
}
lval.str = s[1:len(s)-1] // remove the two quotes
return STRING
}
/\-?[0-9]+/
{
yylex.pos(lval) // our pos
s := yylex.Text()
var err error
lval.int, err = strconv.ParseInt(s, 10, 64) // int64
if err == nil {
return INTEGER
} else if e := err.(*strconv.NumError); e.Err == strconv.ErrRange {
// this catches range errors for very large ints
lp := yylex.cast()
lp.lexerErr = &LexParseErr{
Err: ErrLexerIntegerOverflow,
Str: s,
Row: yylex.Line(),
Col: yylex.Column(),
}
return ERROR
} else {
panic(fmt.Sprintf("error lexing INTEGER, got: %v", err))
}
}
/\-?[0-9]+\.[0-9]+/
{
yylex.pos(lval) // our pos
s := yylex.Text()
var err error
lval.float, err = strconv.ParseFloat(s, 64) // float64
if err == nil {
return FLOAT
} else if e := err.(*strconv.NumError); e.Err == strconv.ErrRange {
// this catches range errors for very large floats
lp := yylex.cast()
lp.lexerErr = &LexParseErr{
Err: ErrLexerFloatOverflow,
Str: s,
Row: yylex.Line(),
Col: yylex.Column(),
}
return ERROR
} else {
panic(fmt.Sprintf("error lexing FLOAT, got: %v", err))
}
}
/\$[a-z]+([a-z0-9_]*[a-z0-9]+)?{[0-9]+}/
{
// we have this as a single token, because otherwise the
// parser can get confused by the curly brackets :/
yylex.pos(lval) // our pos
s := yylex.Text()
s = s[1:len(s)] // remove the leading $
s = s[0:len(s)-1] // remove the trailing close curly
// XXX: nex has a bug that it gets confused by the
// following single curly brace. Please see:
// https://github.com/blynn/nex/issues/48
a := strings.Split(s, "{") // XXX: close match here: }
if len(a) != 2 {
panic(fmt.Sprintf("error lexing VAR_IDENTIFIER_HX: %v", a))
}
lval.str = a[0]
var err error
lval.int, err = strconv.ParseInt(a[1], 10, 64) // int64
if err == nil {
return VAR_IDENTIFIER_HX
} else if e := err.(*strconv.NumError); e.Err == strconv.ErrRange {
// this catches range errors for very large ints
lp := yylex.cast()
lp.lexerErr = &LexParseErr{
Err: ErrLexerIntegerOverflow,
Str: a[1],
Row: yylex.Line(),
Col: yylex.Column(),
}
return ERROR
} else {
panic(fmt.Sprintf("error lexing VAR_IDENTIFIER_HX, got: %v", err))
}
}
/\$[a-z]([a-z0-9_]*[a-z0-9]+)?/
{
// an alternate pattern: /\$[a-z](|[a-z0-9_]*[a-z0-9])/
yylex.pos(lval) // our pos
s := yylex.Text()
lval.str = s[1:len(s)] // remove the leading $
return VAR_IDENTIFIER
}
/[a-z]([a-z0-9_]*[a-z0-9]+)?/
{
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return IDENTIFIER
}
/[A-Z]([a-z0-9_]*[a-z0-9]+)?/
{
yylex.pos(lval) // our pos
s := yylex.Text()
lval.str = strings.ToLower(s) // uncapitalize it
return CAPITALIZED_IDENTIFIER
}
/[a-z]([a-z0-9:]*[a-z0-9]+)?/
{
yylex.pos(lval) // our pos
lval.str = yylex.Text()
return RES_IDENTIFIER
}
/#[^\n]*/
{ // this matches a (#) pound char followed by any
// number of chars that aren't the (\n) newline!
yylex.pos(lval) // our pos
s := yylex.Text()
lval.str = s[1:len(s)] // remove the leading #
//log.Printf("lang: lexer: comment: `%s`", lval.str)
//return COMMENT // skip return to avoid parsing
}
/./ {
yylex.pos(lval) // our pos
s := yylex.Text()
lp := yylex.cast()
e := ErrLexerUnrecognized
if s == "\r" { // windows!
e = ErrLexerUnrecognizedCR
}
lp.lexerErr = &LexParseErr{
Err: e,
Str: s,
Row: yylex.Line(),
Col: yylex.Column(),
}
return ERROR
}
//
// Mgmt
// Copyright (C) 2013-2021+ James Shubin and the project contributors
// Written by James Shubin <james@shubin.ca> and the project contributors
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package lang
import (
"fmt"
"strconv"
"github.com/purpleidea/mgmt/lang/interfaces"
)
// NOTE:
// Among rules in the same scope, the longest matching pattern takes precedence.
// In event of a tie, the first pattern wins.