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diff --git a/_doc/example.rst b/_doc/example.rst deleted file mode 100644 index a2cdf78..0000000 --- a/_doc/example.rst +++ /dev/null @@ -1,211 +0,0 @@ -******** -Examples -******** - -Basic round trip of parsing YAML to Python objects, modifying -and generating YAML:: - - import sys - from ruamel.yaml import YAML - - inp = """\ - # example - name: - # details - family: Smith # very common - given: Alice # one of the siblings - """ - - yaml = YAML() - code = yaml.load(inp) - code['name']['given'] = 'Bob' - - yaml.dump(code, sys.stdout) - -Resulting in:: - - # example - name: - # details - family: Smith # very common - given: Bob # one of the siblings - -with the old API:: - - from __future__ import print_function - - import sys - import ruamel.yaml - - inp = """\ - # example - name: - # details - family: Smith # very common - given: Alice # one of the siblings - """ - - code = ruamel.yaml.load(inp, ruamel.yaml.RoundTripLoader) - code['name']['given'] = 'Bob' - - ruamel.yaml.dump(code, sys.stdout, Dumper=ruamel.yaml.RoundTripDumper) - - # the last statement can be done less efficient in time and memory with - # leaving out the end='' would cause a double newline at the end - # print(ruamel.yaml.dump(code, Dumper=ruamel.yaml.RoundTripDumper), end='') - -Resulting in :: - - # example - name: - # details - family: Smith # very common - given: Bob # one of the siblings - ----- - -YAML handcrafted anchors and references as well as key merging -are preserved. The merged keys can transparently be accessed -using ``[]`` and ``.get()``:: - - from ruamel.yaml import YAML - - inp = """\ - - &CENTER {x: 1, y: 2} - - &LEFT {x: 0, y: 2} - - &BIG {r: 10} - - &SMALL {r: 1} - # All the following maps are equal: - # Explicit keys - - x: 1 - y: 2 - r: 10 - label: center/big - # Merge one map - - <<: *CENTER - r: 10 - label: center/big - # Merge multiple maps - - <<: [*CENTER, *BIG] - label: center/big - # Override - - <<: [*BIG, *LEFT, *SMALL] - x: 1 - label: center/big - """ - - yaml = YAML() - data = yaml.load(inp) - assert data[7]['y'] == 2 - - -The ``CommentedMap``, which is the ``dict`` like construct one gets when round-trip loading, -supports insertion of a key into a particular position, while optionally adding a comment:: - - import sys - from ruamel.yaml import YAML - - yaml_str = """\ - first_name: Art - occupation: Architect # This is an occupation comment - about: Art Vandelay is a fictional character that George invents... - """ - - yaml = YAML() - data = yaml.load(yaml_str) - data.insert(1, 'last name', 'Vandelay', comment="new key") - yaml.dump(data, sys.stdout) - -gives:: - - first_name: Art - last name: Vandelay # new key - occupation: Architect # This is an occupation comment - about: Art Vandelay is a fictional character that George invents... - -Please note that the comment is aligned with that of its neighbour (if available). - -The above was inspired by a `question <http://stackoverflow.com/a/36970608/1307905>`_ -posted by *demux* on StackOverflow. - ----- - -By default ``ruamel.yaml`` indents with two positions in block style, for -both mappings and sequences. For sequences the indent is counted to the -beginning of the scalar, with the dash taking the first position of the -indented "space". - -The following program with three dumps:: - - import sys - from ruamel.yaml import YAML - - data = {1: {1: [{1: 1, 2: 2}, {1: 1, 2: 2}], 2: 2}, 2: 42} - - yaml = YAML() - yaml.explicit_start = True - yaml.dump(data, sys.stdout) - yaml.indent = 4 - yaml.block_seq_indent = 2 - yaml.dump(data, sys.stdout) - - - def sequence_indent_four(s): - # this will fail on direclty nested lists: {1; [[2, 3], 4]} - levels = [] - ret_val = '' - for line in s.splitlines(True): - ls = line.lstrip() - indent = len(line) - len(ls) - if ls.startswith('- '): - if not levels or indent > levels[-1]: - levels.append(indent) - elif levels: - if indent < levels[-1]: - levels = levels[:-1] - # same -> do nothing - else: - if levels: - if indent <= levels[-1]: - while levels and indent <= levels[-1]: - levels = levels[:-1] - ret_val += ' ' * len(levels) + line - return ret_val - - yaml = YAML() - yaml.explicit_start = True - yaml.dump(data, sys.stdout, transform=sequence_indent_four) - -gives as output:: - - --- - 1: - 1: - - 1: 1 - 2: 2 - - 1: 1 - 2: 2 - 2: 2 - 2: 42 - --- - 1: - 1: - - 1: 1 - 2: 2 - - 1: 1 - 2: 2 - 2: 2 - 2: 42 - --- - 1: - 1: - - 1: 1 - 2: 2 - - 1: 1 - 2: 2 - 2: 2 - 2: 42 - -The transform example was inspired by a `question -<https://stackoverflow.com/q/44388701/1307905>`_ posted by *nowox* on -StackOverflow. |