Metode template

Regular Expressions in Python

Maria Eugenia Inzaugarat

Data Scientist

Template string

Sintaks lebih sederhana
Lebih lambat daripada f-string
Terbatas: tidak mendukung format specifier
Cocok saat bekerja dengan string berformat eksternal

Sintaks dasar

from string import Template

my_string = Template('Data science has been called $identifier')

my_string.substitute(identifier="sexiest job of the 21st century")

'Data science has been called sexiest job of the 21st century'

Substitusi

Gunakan banyak $identifier
Gunakan variabel

from string import Template
job = "Data science"
name = "sexiest job of the 21st century"

my_string = Template('$title has been called $description')

my_string.substitute(title=job, description=name)

'Data science has been called sexiest job of the 21st century'

Substitusi

Pakai ${identifier} saat ada karakter valid setelah identifier

my_string = Template('I find Python very ${noun}ing but my sister has lost $noun')

my_string.substitute(noun="interest")

'I find Python very interesting but my sister has lost interest'

Substitusi

Gunakan $$ untuk escape tanda dolar

my_string = Template('I paid for the Python course only $$ $price, amazing!')

my_string.substitute(price="12.50")

'I paid for the Python course only $ 12.50, amazing!'

Substitusi

Munculkan error saat placeholder hilang

favorite = dict(flavor="chocolate")

my_string = Template('I love $flavor $cake very much')

my_string.substitute(favorite)

Traceback (most recent call last):
KeyError: 'cake'

Substitusi

favorite = dict(flavor="chocolate")
my_string = Template('I love $flavor $cake very much')

try:
    my_string.substitute(favorite) 
except KeyError:
      print("missing information")

missing information

Safe substitution

Selalu berupaya mengembalikan string yang dapat dipakai
Placeholder yang hilang akan muncul di hasil string

favorite = dict(flavor="chocolate")
my_string = Template('I love $flavor $cake very much')

my_string.safe_substitute(favorite)

'I love chocolate $cake very much'

Apa yang sebaiknya digunakan?

str.format():
- Bagus untuk mulai. Konsepnya berlaku pada f-string.
- Kompatibel dengan semua versi Python.
f-strings:
- Umumnya paling disarankan.
- Hanya untuk Python modern (3.6+).
Template strings:
- Saat memakai string eksternal atau dari pengguna

Ayo berlatih!

Regular Expressions in Python