B. Grammar
This appendix contains summaries of the lexical and syntactic grammars found in the main document.
Tip
The ~opt~ notation in the syntax definitions indicates that the lexical entity is optional in
the syntax.
B.1 Lexical grammar
input:
input-elements~opt~ signature-block~opt~
input-elements:
input-element
input-elements input-element
input-element:
whitespace
comment
token
signature-block:
signature-begin signature signature-end
signature-begin:
new-line-character # SIG # Begin signature block new-line-character
signature:
base64 encoded signature blob in multiple single-line-comments
signature-end:
new-line-character # SIG # End signature block new-line-character
B.1.1 Line terminators
new-line-character:
Carriage return character (U+000D)
Line feed character (U+000A)
Carriage return character (U+000D) followed by line feed character (U+000A)
new-lines:
new-line-character
new-lines new-line-character
B.1.2 Comments
comment:
single-line-comment
requires-comment
delimited-comment
single-line-comment:
# input-characters~opt~
input-characters:
input-character
input-characters input-character
input-character:
Any Unicode character except a new-line-character
requires-comment:
#requires whitespace command-arguments
dash:
- (U+002D)
EnDash character (U+2013)
EmDash character (U+2014)
Horizontal bar character (U+2015)
dashdash:
dash dash
delimited-comment:
<# delimited-comment-text~opt~ hashes >
delimited-comment-text:
delimited-comment-section
delimited-comment-text delimited-comment-section
delimited-comment-section:
>
hashes~opt~ not-greater-than-or-hash
hashes:
#
hashes #
not-greater-than-or-hash:
Any Unicode character except > or #
B.1.3 White space
whitespace:
Any character with Unicode class Zs, Zl, or Zp
Horizontal tab character (U+0009)
Vertical tab character (U+000B)
Form feed character (U+000C)
` (The backtick character U+0060) followed by new-line-character
B.1.4 Tokens
token:
keyword
variable
command
command-parameter
command-argument-token
integer-literal
real-literal
string-literal
type-literal
operator-or-punctuator
B.1.5 Keywords
keyword: one of
begin break catch class
continue data define do
dynamicparam else elseif end
exit filter finally for
foreach from function if
in inlinescript parallel param
process return switch throw
trap try until using
var while workflow
B.1.6 Variables
variable:
$$
$?
$^
$ variable-scope~opt~ variable-characters
@ variable-scope~opt~ variable-characters
braced-variable
braced-variable:
${ variable-scope~opt~ braced-variable-characters }
variable-scope:
global:
local:
private:
script:
using:
workflow:
variable-namespace
variable-namespace:
variable-characters :
variable-characters:
variable-character
variable-characters variable-character
variable-character:
A Unicode character of classes Lu, Ll, Lt, Lm, Lo, or Nd
_ (The underscore character U+005F)
?
braced-variable-characters:
braced-variable-character
braced-variable-characters braced-variable-character
braced-variable-character:
Any Unicode character except
} (The closing curly brace character U+007D)
` (The backtick character U+0060)
escaped-character
escaped-character:
` (The backtick character U+0060) followed by any Unicode character
B.1.7 Commands
generic-token:
generic-token-parts
generic-token-parts:
generic-token-part
generic-token-parts generic-token-part
generic-token-part:
expandable-string-literal
verbatim-here-string-literal
variable
generic-token-char
generic-token-char:
Any Unicode character except
{ } ( ) ; , | & $
` (The backtick character U+0060)
double-quote-character
single-quote-character
whitespace
new-line-character
escaped-character
generic-token-with-subexpr-start:
generic-token-parts $(
B.1.8 Parameters
command-parameter:
dash first-parameter-char parameter-chars colon~opt~
first-parameter-char:
A Unicode character of classes Lu, Ll, Lt, Lm, or Lo
_ (The underscore character U+005F)
?
parameter-chars:
parameter-char
parameter-chars parameter-char
parameter-char:
Any Unicode character except
{ } ( ) ; , | & . [
colon
whitespace
new-line-character
colon:
: (The colon character U+003A)
verbatim-command-argument-chars:
verbatim-command-argument-part
verbatim-command-argument-chars verbatim-command-argument-part
verbatim-command-argument-part:
verbatim-command-string
& non-ampersand-character
Any Unicode character except
|
new-line-character
non-ampersand-character:
Any Unicode character except &
verbatim-command-string:
double-quote-character non-double-quote-chars
double-quote-character
non-double-quote-chars:
non-double-quote-char
non-double-quote-chars non-double-quote-char
non-double-quote-char:
Any Unicode character except
double-quote-character
B.1.9 Literals
literal:
integer-literal
real-literal
string-literal
B.1.9.1 Integer Literals
integer-literal:
decimal-integer-literal
hexadecimal-integer-literal
decimal-integer-literal:
decimal-digits numeric-type-suffix~opt~ numeric-multiplier~opt~
decimal-digits:
decimal-digit
decimal-digit decimal-digits
decimal-digit: one of
0 1 2 3 4 5 6 7 8 9
numeric-type-suffix:
long-type-suffix
decimal-type-suffix
hexadecimal-integer-literal:
0x hexadecimal-digits long-type-suffix~opt~
numeric-multiplier~opt~
hexadecimal-digits:
hexadecimal-digit
hexadecimal-digit decimal-digits
hexadecimal-digit: one of
0 1 2 3 4 5 6 7 8 9 a b c d e f
long-type-suffix:
l
numeric-multiplier: one of
kb mb gb tb pb
B.1.9.2 Real Literals
real-literal:
decimal-digits . decimal-digits exponent-part~opt~ decimal-type-suffix~opt~ numeric-multiplier~opt~
. decimal-digits exponent-part~opt~ decimal-type-suffix~opt~ numeric-multiplier~opt~
decimal-digits exponent-part decimal-type-suffix~opt~ numeric-multiplier~opt~
exponent-part:
e sign~opt~ decimal-digits
sign: one of
+
dash
decimal-type-suffix:
d
l
B.1.9.3 String Literals
string-literal:
expandable-string-literal
expandable-here-string-literal
verbatim-string-literal
verbatim-here-string-literal
expandable-string-literal:
double-quote-character expandable-string-characters~opt~ dollars~opt~ double-quote-character
double-quote-character:
" (U+0022)
Left double quotation mark (U+201C)
Right double quotation mark (U+201D)
Double low-9 quotation mark (U+201E)
expandable-string-characters:
expandable-string-part
expandable-string-characters
expandable-string-part
expandable-string-part:
Any Unicode character except
$
double-quote-character
` (The backtick character U+0060)
braced-variable
$ Any Unicode character except
(
{
double-quote-character
` (The backtick character U+0060)*
$ escaped-character
escaped-character
double-quote-character double-quote-character
dollars:
$
dollars $
expandable-here-string-literal:
@ double-quote-character whitespace~opt~ new-line-character
expandable-here-string-characters~opt~ new-line-character double-quote-character @
expandable-here-string-characters:
expandable-here-string-part
expandable-here-string-characters expandable-here-string-part
expandable-here-string-part:
Any Unicode character except
$
new-line-character
braced-variable
$ Any Unicode character except
(
new-line-character
$ new-line-character Any Unicode character except double-quote-char
$ new-line-character double-quote-char Any Unicode character except @
new-line-character Any Unicode character except double-quote-char
new-line-character double-quote-char Any Unicode character except @
expandable-string-with-subexpr-start:
double-quote-character expandable-string-chars~opt~ $(
expandable-string-with-subexpr-end:
double-quote-char
expandable-here-string-with-subexpr-start:
@ double-quote-character whitespace~opt~ new-line-character expandable-here-string-chars~opt~ $(
expandable-here-string-with-subexpr-end:
new-line-character double-quote-character @
verbatim-string-literal:
single-quote-character verbatim-string-characters~opt~ single-quote-char
single-quote-character:
' (U+0027)
Left single quotation mark (U+2018)
Right single quotation mark (U+2019)
Single low-9 quotation mark (U+201A)
Single high-reversed-9 quotation mark (U+201B)
verbatim-string-characters:
verbatim-string-part
verbatim-string-characters verbatim-string-part
verbatim-string-part:
*Any Unicode character except* single-quote-character
single-quote-character single-quote-character
verbatim-here-string-literal:
@ single-quote-character whitespace~opt~ new-line-character
verbatim-here-string-characters~opt~ new-line-character
single-quote-character *@*
verbatim-*here-string-characters:
verbatim-here-string-part
verbatim-here-string-characters verbatim-here-string-part
verbatim-here-string-part:
Any Unicode character except* new-line-character
new-line-character Any Unicode character except single-quote-character
new-line-character single-quote-character Any Unicode character except @
B.1.10 Simple Names
simple-name:
simple-name-first-char simple-name-chars
simple-name-first-char:
A Unicode character of classes Lu, Ll, Lt, Lm, or Lo
_ (The underscore character U+005F)
simple-name-chars:
simple-name-char
simple-name-chars simple-name-char
simple-name-char:
A Unicode character of classes Lu, Ll, Lt, Lm, Lo, or Nd
_ (The underscore character U+005F)
B.1.11 Type Names
type-name:
type-identifier
type-name . type-identifier
type-identifier:
type-characters
type-characters:
type-character
type-characters type-character
type-character:
A Unicode character of classes Lu, Ll, Lt, Lm, Lo, or Nd
_ (The underscore character U+005F)
array-type-name:
type-name [
generic-type-name:
type-name [
B.1.12 Operators and punctuators
operator-or-punctuator: one of
{ } [ ] ( ) @( @{ $( ;
&& || & | , ++ .. :: .
! * / % +
dash dashdash
dash and dash band dash bnot dash bor
dash bxor dash not dash or dash xor
assignment-operator
merging-redirection-operator
file-redirection-operator
comparison-operator
format-operator
assignment-operator: one of
= dash = += *= /= %=
file-redirection-operator: one of
> >> 2> 2>> 3> 3>> 4> 4>>
5> 5>> 6> 6>> *> *>> <
merging-redirection-operator: one of
*>&1 2>&1 3>&1 4>&1 5>&1 6>&1
*>&2 1>&2 3>&2 4>&2 5>&2 6>&2
comparison-operator: one of
dash as dash ccontains dash ceq
dash cge dash cgt dash cle
dash clike dash clt dash cmatch
dash cne dash cnotcontains dash cnotlike
dash cnotmatch dash contains dash creplace
dash csplit dash eq dash ge
dash gt dash icontains dash ieq
dash ige dash igt dash ile
dash ilike dash ilt dash imatch
dash in dash ine dash inotcontains
dash inotlike dash inotmatch dash ireplace
dash is dash isnot dash isplit
dash join dash le dash like
dash lt dash match dash ne
dash notcontains dash notin dash notlike
dash notmatch dash replace dash shl*
dash shr dash split
format-operator:
dash f
B.2 Syntactic grammar
B.2.1 Basic concepts
script-file:
script-block
module-file:
script-block
interactive-input:
script-block
data-file:
statement-list
B.2.2 Statements
script-block:
param-block~opt~ statement-terminators~opt~ script-block-body~opt~
param-block:
new-lines~opt~ attribute-list~opt~ new-lines~opt~ param new-lines~opt~
( parameter-list~opt~ new-lines~opt~ )
parameter-list:
script-parameter
parameter-list new-lines~opt~ , script-parameter
script-parameter:
new-lines~opt~ attribute-list~opt~ new-lines~opt~ variable script-parameter-default~opt~
script-parameter-default:
new-lines~opt~ = new-lines~opt~ expression
script-block-body:
named-block-list
statement-list
named-block-list:
named-block
named-block-list named-block
named-block:
block-name statement-block statement-terminators~opt~
block-name: one of
dynamicparam begin process end
statement-block:
new-lines~opt~ { statement-list~opt~ new-lines~opt~ }
statement-list:
statement
statement-list statement
statement:
if-statement
label~opt~ labeled-statement
function-statement
flow-control-statement statement-terminator
trap-statement
try-statement
data-statement
inlinescript-statement
parallel-statement
sequence-statement
pipeline statement-terminator
statement-terminator:
;
new-line-character
statement-terminators:
statement-terminator
statement-terminators statement-terminator
if-statement:
if new-lines~opt~ ( new-lines~opt~ pipeline new-lines~opt~ ) statement-block
elseif-clauses~opt~ else-clause~opt~
elseif-clauses:
elseif-clause
elseif-clauses elseif-clause
elseif-clause:
new-lines~opt~ elseif new-lines~opt~ ( new-lines~opt~ pipeline new-lines~opt~ ) statement-block
else-clause:
new-lines~opt~ else statement-block
labeled-statement:
switch-statement
foreach-statement
for-statement
while-statement
do-statement
switch-statement:
switch new-lines~opt~ switch-parameters~opt~ switch-condition switch-body
switch-parameters:
switch-parameter
switch-parameters switch-parameter
switch-parameter:
-regex
-wildcard
-exact
-casesensitive
-parallel
switch-condition:
( new-lines~opt~ pipeline new-lines~opt~ )
-file new-lines~opt~ switch-filename
switch-filename:
command-argument
primary-expression
switch-body:
new-lines~opt~ { new-lines~opt~ switch-clauses }
switch-clauses:
switch-clause
switch-clauses switch-clause
switch-clause:
switch-clause-condition statement-block statement-terimators~opt~
switch-clause-condition:
command-argument
primary-expression
foreach-statement:
foreach new-lines~opt~ foreach-parameter~opt~ new-lines~opt~
( new-lines~opt~ variable new-lines~opt~ in new-lines~opt~ pipeline
new-lines~opt~ ) statement-block
foreach-parameter:
-parallel
for-statement:
for new-lines~opt~ (
new-lines~opt~ for-initializer~opt~ statement-terminator
new-lines~opt~ for-condition~opt~ statement-terminator
new-lines~opt~ for-iterator~opt~
new-lines~opt~ ) statement-block
for new-lines~opt~ (
new-lines~opt~ for-initializer~opt~ statement-terminator
new-lines~opt~ for-condition~opt~
new-lines~opt~ ) statement-block
for new-lines~opt~ (
new-lines~opt~ for-initializer~opt~
new-lines~opt~ ) statement-block
for-initializer:
pipeline
for-condition:
pipeline
for-iterator:
pipeline
while-statement:
while new-lines~opt~ ( new-lines~opt~ while-condition new-lines~opt~ ) statement-block
do-statement:
do statement-block new-lines~opt~ while new-lines~opt~ ( while-condition new-lines~opt~ )
do statement-block new-lines~opt~ until new-lines~opt~ ( while-condition new-lines~opt~ )
while-condition:
new-lines~opt~ pipeline
function-statement:
function new-lines~opt~ function-name function-parameter-declaration~opt~ { script-block }
filter new-lines~opt~ function-name function-parameter-declaration~opt~ { script-block }
workflow new-lines~opt~ function-name function-parameter-declaration~opt~ { script-block }
function-name:
command-argument
function-parameter-declaration:
new-lines~opt~ ( parameter-list new-lines~opt~ )
flow-control-statement:
break label-expression~opt~
continue label-expression~opt~
throw pipeline~opt~
return pipeline~opt~
exit pipeline~opt~
label-expression:
simple-name
unary-expression
trap-statement:
trap new-lines~opt~ type-literal~opt~ new-lines~opt~ statement-block
try-statement:
try statement-block catch-clauses
try statement-block finally-clause
try statement-block catch-clauses finally-clause
catch-clauses:
catch-clause
catch-clauses catch-clause
catch-clause:
new-lines~opt~ catch catch-type-list~opt~ statement-block
catch-type-list:
new-lines~opt~ type-literal
catch-type-list new-lines~opt~ , new-lines~opt~ type-literal
finally-clause:
new-lines~opt~ finally statement-block
data-statement:
data new-lines~opt~ data-name data-commands-allowed~opt~
statement-block
data-name:
simple-name
data-commands-allowed:
new-lines~opt~ -supportedcommand data-commands-list
data-commands-list:
new-lines~opt~ data-command
data-commands-list , new-lines~opt~ data-command
data-command:
command-name-expr
inlinescript-statement:
inlinescript statement-block
parallel-statement:
parallel statement-block
sequence-statement:
sequence statement-block
pipeline:
assignment-expression
expression redirections~opt~ pipeline-tail~opt~
command verbatim-command-argument~opt~ pipeline-tail~opt~
assignment-expression:
expression assignment-operator statement
pipeline-tail:
| new-lines~opt~ command
| new-lines~opt~ command pipeline-tail
command:
command-name command-elements~opt~
command-invocation-operator command-module~opt~ command-name-expr command-elements~opt~
command-invocation-operator: one of
& .
command-module:
primary-expression
command-name:
generic-token
generic-token-with-subexpr
generic-token-with-subexpr:
No whitespace is allowed between ) and command-name.
generic-token-with-subexpr-start statement-list~opt~ ) command-name
command-name-expr:
command-name
primary-expression
command-elements:
command-element
command-elements command-element
command-element:
command-parameter
command-argument
redirection
command-argument:
command-name-expr
verbatim-command-argument:
--% verbatim-command-argument-chars
redirections:
redirection
redirections redirection
redirection:
merging-redirection-operator
file-redirection-operator redirected-file-name
redirected-file-name:
command-argument
primary-expression
B.2.3 Expressions
expression:
logical-expression
logical-expression:
bitwise-expression
logical-expression -and new-lines~opt~ bitwise-expression
logical-expression -or new-lines~opt~ bitwise-expression
logical-expression -xor new-lines~opt~ bitwise-expression
bitwise-expression:
comparison-expression
bitwise-expression -band new-lines~opt~ comparison-expression
bitwise-expression -bor new-lines~opt~ comparison-expression
bitwise-expression -bxor new-lines~opt~ comparison-expression
comparison-expression:
additive-expression
comparison-expression comparison-operator new-lines~opt~
additive-expression
additive-expression:
multiplicative-expression
additive-expression + new-lines~opt~ multiplicative-expression
additive-expression dash new-lines~opt~ multiplicative-expression
multiplicative-expression:
format-expression
multiplicative-expression \ new-lines~opt~ format-expression
multiplicative-expression / new-lines~opt~ format-expression
multiplicative-expression % new-lines~opt~ format-expression
format-expression:
range-expression
format-expression format-operator new-lines~opt~ range-expression
range-expression:
array-literal-expression
range-expression .. new-lines~opt~ array-literal-expression
array-literal-expression:
unary-expression
unary-expression , new-lines~opt~ array-literal-expression
unary-expression:
primary-expression
expression-with-unary-operator
expression-with-unary-operator:
, new-lines~opt~ unary-expression
-not new-lines~opt~ unary-expression
! new-lines~opt~ unary-expression
-bnot new-lines~opt~ unary-expression
+ new-lines~opt~ unary-expression
dash new-lines~opt~ unary-expression
pre-increment-expression
pre-decrement-expression
cast-expression
-split new-lines~opt~ unary-expression
-join new-lines~opt~ unary-expression
pre-increment-expression:
++ new-lines~opt~ unary-expression
pre-decrement-expression:
dashdash new-lines~opt~ unary-expression
cast-expression:
type-literal unary-expression
attributed-expression:
type-literal variable
primary-expression:
value
member-access
element-access
invocation-expression
post-increment-expression
post-decrement-expression
value:
parenthesized-expression
sub-expression
array-expression
script-block-expression
hash-literal-expression
literal
type-literal
variable
parenthesized-expression:
( new-lines~opt~ pipeline new-lines~opt~ )
sub-expression:
$( new-lines~opt~ statement-list~opt~ new-lines~opt~ )
array-expression:
@( new-lines~opt~ statement-list~opt~ new-lines~opt~ )
script-block-expression:
{ new-lines~opt~ script-block new-lines~opt~ }
hash-literal-expression:
@{ new-lines~opt~ hash-literal-body~opt~ new-lines~opt~ }
hash-literal-body:
hash-entry
hash-literal-body statement-terminators hash-entry
hash-entry:
key-expression = new-lines~opt~ statement
key-expression:
simple-name
unary-expression
post-increment-expression:
primary-expression ++
post-decrement-expression:
primary-expression dashdash
member-access: Note no whitespace is allowed after
primary-expression.
primary-expression . member-name
primary-expression :: member-name
element-access: Note no whitespace is allowed between primary-expression and [.
primary-expression [ new-lines~opt~ expression new-lines~opt~ ]
invocation-expression: Note no whitespace is allowed after
primary-expression.
primary-expression . member-name argument-list
primary-expression :: member-name argument-list
argument-list:
( argument-expression-list~opt~ new-lines~opt~ )
argument-expression-list:
argument-expression
argument-expression new-lines~opt~ , argument-expression-list
argument-expression:
new-lines~opt~ logical-argument-expression
logical-argument-expression:
bitwise-argument-expression
logical-argument-expression -and new-lines~opt~ bitwise-argument-expression
logical-argument-expression -or new-lines~opt~ bitwise-argument-expression
logical-argument-expression -xor new-lines~opt~ bitwise-argument-expression
bitwise-argument-expression:
comparison-argument-expression
bitwise-argument-expression -band new-lines~opt~ comparison-argument-expression
bitwise-argument-expression -bor new-lines~opt~ comparison-argument-expression
bitwise-argument-expression -bxor new-lines~opt~ comparison-argument-expression
comparison-argument-expression:
additive-argument-expression
comparison-argument-expression comparison-operator
new-lines~opt~ additive-argument-expression
additive-argument-expression:
multiplicative-argument-expression
additive-argument-expression + new-lines~opt~ multiplicative-argument-expression
additive-argument-expression dash new-lines~opt~ multiplicative-argument-expression
multiplicative-argument-expression:
format-argument-expression
multiplicative-argument-expression \ new-lines~opt~ format-argument-expression
multiplicative-argument-expression / new-lines~opt~ format-argument-expression
multiplicative-argument-expression % new-lines~opt~ format-argument-expression
format-argument-expression:
range-argument-expression
format-argument-expression format-operator new-lines~opt~ range-argument-expression
range-argument-expression:
unary-expression
range-expression .. new-lines~opt~ unary-expression
member-name:
simple-name
string-literal
string-literal-with-subexpression
expression-with-unary-operator
value
string-literal-with-subexpression:
expandable-string-literal-with-subexpr
expandable-here-string-literal-with-subexpr
expandable-string-literal-with-subexpr:
expandable-string-with-subexpr-start statement-list~opt~ )
expandable-string-with-subexpr-characters expandable-string-with-subexpr-end
expandable-here-string-with-subexpr-start statement-list~opt~ )
expandable-here-string-with-subexpr-characters
expandable-here-string-with-subexpr-end
expandable-string-with-subexpr-characters:
expandable-string-with-subexpr-part
expandable-string-with-subexpr-characters expandable-string-with-subexpr-part
expandable-string-with-subexpr-part:
sub-expression
expandable-string-part
expandable-here-string-with-subexpr-characters:
expandable-here-string-with-subexpr-part
expandable-here-string-with-subexpr-characters expandable-here-string-with-subexpr-part
expandable-here-string-with-subexpr-part:
sub-expression
expandable-here-string-part
type-literal:
[ type-spec ]
type-spec:
array-type-name new-lines~opt~ dimension~opt~ ]
generic-type-name new-lines~opt~ generic-type-arguments ]
type-name
dimension:
,
dimension ,
generic-type-arguments:
type-spec new-lines~opt~
generic-type-arguments , new-lines~opt~ type-spec
B.2.4 Attributes
attribute-list:
attribute
attribute-list new-lines~opt~ attribute
attribute:
[ new-lines~opt~ attribute-name ( attribute-arguments new-lines~opt~ ) new-lines~opt~ ]
type-literal
attribute-name:
type-spec
attribute-arguments:
attribute-argument
attribute-argument new-lines~opt~ , attribute-arguments
attribute-argument:
new-lines~opt~ expression
new-lines~opt~ simple-name
new-lines~opt~ simple-name = new-lines~opt~ expression
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