Regular Expressions 101

Pro

Positive Lookbehind(?<=gene=)

gene=the literal text gene= (case sensitive)

.+?any Unicode character (except for line terminators), repeated at least once

Positive Lookahead(?=\])

\]the literal ] (93₁₀ / 135₈ / 5D₁₆)

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

25 tokens

Regular Expression

(?<=gene=).+?(?=\])

New

>lcl|NC_001802.1_cds_NP_057851.1_3 [gene=vif] [locus_tag=HIV1gp3] [db_xref=GeneID:155459] [protein=Vif] [protein_id=NP_057851.1] [location=4587..5165] [gbkey=CDS]

Extraction

>lcl|NC_001802.1_cds_NP_057851.1_3 [gene=vif] [locus_tag=HIV1gp3] [db_xref=GeneID:155459] [protein=Vif] [protein_id=NP_057851.1] [location=4587..5165] [gbkey=CDS]