CODEWITHSUNDEEP
python
Qiang Li
Qiang Li

Reputation: 10855

why this way of executing python isn't working

python -c 'for i in range(10): print i'

works, and 

python -c 'a=3;'

works, but 

python -c 'a=3;for i in range(10): print i'

gave an error

  File "<string>", line 1
    a=3;for i in range(10): print i
          ^
SyntaxError: invalid syntax

Could anyone help point out why? Thank you.

Upvotes: 2

Views: 82

Answers (2)

Amadan
Amadan

Reputation: 198324

Because that's how Python syntax works. for, like all other statements that introduce an indent level, does not like having anything in front of it.

You need a newline in this case, not a semicolon. These are legal (assuming bash):

python -c 'a=3
for i in range(10)]: print(i)'

python -c $'a=3\nfor i in range(10): print(i)'

Upvotes: 5

Snild Dolkow
Snild Dolkow

Reputation: 6866

; can only be used to separate "simple" statements, not compound statements.

https://docs.python.org/3/reference/compound_stmts.html

compound_stmt ::=  if_stmt
                   | while_stmt
                   | for_stmt
                   | try_stmt
                   | with_stmt
                   | funcdef
                   | classdef
                   | async_with_stmt
                   | async_for_stmt
                   | async_funcdef
suite         ::=  stmt_list NEWLINE | NEWLINE INDENT statement+ DEDENT
statement     ::=  stmt_list NEWLINE | compound_stmt
stmt_list     ::=  simple_stmt (";" simple_stmt)* [";"]

Upvotes: 4

Related Questions